# Kansas's 4th District margin of victory

Kansas's 4th District

Updated: May 10, 2026

Category: Elections

Tags: US Elections

HTML: /markets/elections/us-elections/kansas-s-4th-district-margin-of-victory/

## Short Answer

**Key takeaway.** Both the **model** and the **market** expect Republicans to win Kansas's 4th District by 8 or more points, with no compelling evidence of mispricing.

## Key Claims (January 2026)

**- - Kansas's 4th District consistently favors Republicans with large victory margins.** - Non-partisan forecasters consistently rate the district as "Solid Republican."
- Sedgwick County exhibits a sustained Republican voter registration advantage since 2020.
- Candidate profiles or political events may plausibly shift the expected margin.
- Prediction markets generally indicate a strong likelihood of a Republican victory.

### Why This Matters (GEO)

- AI agents extract claims, not arguments.
- Improves citation probability in summaries and answer cards.
- Enables fact stitching across multiple sources.

## Executive Verdict

**Key takeaway.** **Model**'s **80.2%** **probability** slightly exceeds 80c **market** (1.2x payout), reflecting strong Republican margins.

### Who Wins and Why

| Outcome | Market | Model | Why |
| --- | --- | --- | --- |
| Republicans, 23+ pts | 30.0% | 32.7% | The district's history, high partisan index, and expert ratings strongly indicate a large Republican victory in 2026. |
| Republicans, 8+ pts | 80.0% | 80.2% | The district's history, high partisan index, and expert ratings strongly indicate a large Republican victory in 2026. |
| Republicans, 11+ pts | 73.0% | 73.4% | The district's history, high partisan index, and expert ratings strongly indicate a large Republican victory in 2026. |

## Model vs Market

| Outcome | Market Probability | Octagon Model Probability |
| --- | --- | --- |
| Republicans, 23+ pts | 30.0% | 32.7% |
| Republicans, 8+ pts | 80.0% | 80.2% |
| Republicans, 11+ pts | 73.0% | 73.4% |
| Republicans, 20+ pts | 50.0% | 51.6% |
| Republicans, 17+ pts | 59.0% | 58.0% |
| Republicans, 32+ pts | 13.0% | 11.0% |
| Republicans, 14+ pts | 0.0% | 60.1% |
| Republicans, 26+ pts | 0.0% | 15.3% |
| Republicans, 29+ pts | 0.0% | 13.0% |

- Expiration: November 3, 2027

## Market Behavior & Price Dynamics

This market has experienced a dramatic upward trend, climbing from an initial price of 1.0% to a peak of 90.1% before settling at its current level of 80.0%. This trajectory includes significant volatility over a short period. A sharp 9.1 percentage point spike occurred on May 7, followed by a 10.1 percentage point drop on May 10. According to the provided context, web research did not identify specific news events or drivers that could be definitively linked to either of these large price movements. The total volume of 880 contracts is moderate, but the sample data points show zero volume on the days of the most significant price swings, which suggests these changes may have been caused by a small number of trades or shifts in standing orders rather than broad market activity.

The price action has established a clear resistance level at the peak of 90.1%. The subsequent drop to 80.0% suggests a potential new support level is forming in that range. Despite the recent decline, the current price of 80.0% indicates a very strong market sentiment that the Republican candidate will win by a significant margin. This high probability aligns with the provided background information on the district's strong Republican lean. The overall price trend shows that market participants quickly priced in the district's historical voting patterns, moving from near-zero probability to a consensus reflecting a likely lopsided victory.

## Significant Price Movements

### Outcome: Republicans, 8+ pts

#### 📉 May 10, 2026: 10.1pp drop

Price decreased from 90.1% to 80.0%

**What happened:** The provided web research did not locate information confirming a 10.1 percentage point drop in the "Kansas's 4th District margin of victory" market for "Republicans, 8+ pts" on May 10, 2026 [[^]](https://kalshi.com/markets/kxmidtermmov/midterm-margin-of-victory/kxmidtermmov-ks04r)[[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner). Consequently, identifying a primary driver, including social media activity, for this specific price movement is not possible with the available sources [[^]](https://kalshi.com/markets/kxmidtermmov/midterm-margin-of-victory/kxmidtermmov-ks04r)[[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner). While Kansas's 4th District is generally considered a safe Republican seat with incumbent Ron Estes, there is no evidence linking any social media posts or other events to the reported drop on that date [[^]](https://www.washingtonpost.com/elections/results/2024/11/05/kansas-house-district-4/)[[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2024)[[^]](https://www.cookpolitical.com/house/race/483121). Therefore, social media's role in this reported movement cannot be determined.

### Outcome: Republicans, 17+ pts

#### 📈 May 07, 2026: 10.0pp spike

Price increased from 49.0% to 59.0%

**What happened:** Web research did not identify a specific cause for a 10.0 percentage point spike in the "Republicans, 17+ pts" outcome for Kansas's 4th District on May 7, 2026 [[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner). A prediction market summary page published on that date reported high Republican probability (approximately 84%) for KS-04, but characterized the situation as low-volatility and explicitly did not attribute any such spike to a specific catalyst [[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner). No social media activity from key figures or traditional news releases were identified that would account for such a movement around that time [[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner). Therefore, social media was not found to be a primary driver or contributing accelerant, as the underlying event and its catalyst were not supported by the research.

## Contract Snapshot

This market resolves to "Yes" if the Republican Party wins the 2026 U.S. House of Representatives election in Kansas's 4th District by 17 percentage points or more; otherwise, it resolves to "No." The margin of victory is calculated as the Republican Party's vote percentage minus the nearest opponent's, with no rounding applied. The market opened on May 5, 2026, and will close upon the publication of certified election results, or by November 3, 2027, with payouts occurring 30 minutes after closing.

## Market Discussion

Kansas's 4th Congressional District is considered a Republican stronghold, evidenced by its R+12 Cook Partisan Voting Index [[^]](https://en.wikipedia.org/wiki/Kansas%27s_4th_congressional_district)[[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026_(August_4_Democratic_primary)). Prediction markets reflect high confidence in a significant Republican victory, with one market showing a 59% chance of a margin of 17 points or more [[^]](https://kalshi.com/markets/kxmidtermmov/midterm-margin-of-victory/kxmidtermmov-ks04r). Historically, even during a 2017 special election with "rumblings of Republican worry," the Republican candidate still won, albeit by a narrower 6.2% margin [[^]](https://en.wikipedia.org/wiki/Kansas%27s_4th_congressional_district)[[^]](https://en.wikipedia.org/wiki/2017_Kansas%27s_4th_congressional_district_special_election)[[^]](https://mcimaps.com/what-to-watch-for-in-the-kansas-4th-district-special-election/).

## Market Data

| Contract | Yes Bid | Yes Ask | Last Price | Volume | Open Interest |
| --- | --- | --- | --- | --- | --- |
| Republicans, 11+ pts | 65% | 72% | 73% | $650 | $100 |
| Republicans, 14+ pts | 56% | 63% | 0% | $0 | $0 |
| Republicans, 17+ pts | 47% | 54% | 59% | $300 | $0 |
| Republicans, 20+ pts | 39% | 46% | 50% | $450 | $0 |
| Republicans, 23+ pts | 30% | 37% | 30% | $907.72 | $3.86 |
| Republicans, 26+ pts | 22% | 29% | 0% | $0 | $0 |
| Republicans, 29+ pts | 13% | 20% | 0% | $0 | $0 |
| Republicans, 32+ pts | 4.8% | 12% | 13% | $20 | $10 |
| Republicans, 8+ pts | 74% | 80% | 80% | $880 | $0 |

## What do historical election results since 2016 in Kansas's 4th District indicate for a baseline Republican margin of victory in 2026?

2016 General Election Republican Margin | 31% [[^]](https://en.wikipedia.org/wiki/2017_Kansas%27s_4th_congressional_district_special_election)[[^]](https://radio.wpsu.org/2017-04-12/gop-holds-kansas-house-seat-as-democrats-surprise-upset-bid-falls-short)[[^]](https://thesunflower.com/17165/news/estes-keeps-4th-district-red-thompson-announces-2018-candidacy/) |
2017 Special Election Republican Margin | 6.2% [[^]](https://en.wikipedia.org/wiki/2017_Kansas%27s_4th_congressional_district_special_election)[[^]](https://radio.wpsu.org/2017-04-12/gop-holds-kansas-house-seat-as-democrats-surprise-upset-bid-falls-short)[[^]](https://thesunflower.com/17165/news/estes-keeps-4th-district-red-thompson-announces-2018-candidacy/) |
2022 General Election Republican Margin | 28% [[^]](https://www.kssos.org/elections/18elec/2018_General_Election_Official_Votes_Cast.pdf) |

**Kansas's 4th Congressional District consistently favors Republicans with substantial victory margins in general elections**

Kansas's 4th Congressional District consistently favors Republicans with substantial victory margins in general elections. This trend was evident in the 2016 General Election when Republican incumbent Mike Pompeo secured a significant **31%** margin over his Democratic opponent [[^]](https://en.wikipedia.org/wiki/2017_Kansas%27s_4th_congressional_district_special_election)[[^]](https://radio.wpsu.org/2017-04-12/gop-holds-kansas-house-seat-as-democrats-surprise-upset-bid-falls-short)[[^]](https://thesunflower.com/17165/news/estes-keeps-4th-district-red-thompson-announces-2018-candidacy/).

A 2017 special election showed a temporary, smaller Republican lead. Following Pompeo's resignation, Republican Ron Estes won this special election with a notably narrower **6.2%** margin [[^]](https://en.wikipedia.org/wiki/2017_Kansas%27s_4th_congressional_district_special_election)[[^]](https://radio.wpsu.org/2017-04-12/gop-holds-kansas-house-seat-as-democrats-surprise-upset-bid-falls-short)[[^]](https://thesunflower.com/17165/news/estes-keeps-4th-district-red-thompson-announces-2018-candidacy/). This result, however, appears to be an outlier, potentially influenced by specific circumstances such as low voter turnout and a strong Democratic challenger present in that particular election [[^]](https://www.kmuw.org/politics/2018-11-07/estes-wins-re-election-in-4th-congressional-district-over-thompson)[[^]](https://radio.wpsu.org/2017-04-12/gop-holds-kansas-house-seat-as-democrats-surprise-upset-bid-falls-short)[[^]](https://www.kcur.org/2018-11-01/little-common-ground-between-estes-thompson-in-4th-congressional-district-race).

Incumbent Ron Estes reestablished substantial Republican margins in later elections. After the 2017 special election, Estes, as the incumbent, consistently increased his lead in general elections. He won the 2018 General Election by **20%** [[^]](https://www.legistorm.com/person/bio/266792/Ronald_Gene_Estes.html)[[^]](https://www.kmuw.org/politics/2018-11-07/estes-wins-re-election-in-4th-congressional-district-over-thompson)[[^]](https://www.kssos.org/elections/18elec/2018_General_Election_Official_Votes_Cast.pdf), the 2020 General Election by **27.3%** [[^]](https://www.legistorm.com/person/bio/266792/Ronald_Gene_Estes.html), and maintained a strong advantage in the 2022 General Election with a **28%** margin [[^]](https://www.kssos.org/elections/18elec/2018_General_Election_Official_Votes_Cast.pdf). These results demonstrate a clear return to the district's typical strong Republican performance.

## How did the political environment of the 2017 special election differ from the expected conditions for the 2026 general election?

2017 Special Election Margin | 6.2% to 7% (Republican victory) [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_special_election,_2017)[[^]](https://en.wikipedia.org/wiki/2017_Kansas%27s_4th_congressional_district_special_election)[[^]](https://time.com/4736025/trump-kansas-special-election-tweet/) |
2026 District Partisan Index | R+12 Cook Partisan Voting Index [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026)[[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026_(August_4_Republican_primary))[[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner) |
2026 Projected Victory Margin | 17 points or more for Republican [[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner)[[^]](https://kalshi.com/markets/kxmidtermmov/kxmidtermmov-ks04r) |

**The 2017 special election differed significantly from 2026 expectations**

The 2017 special election differed significantly from 2026 expectations. In 2017, the Kansas's 4th District special election concluded with an unexpectedly narrow Republican victory, as Ron Estes defeated James Thompson by a margin of **6.2%** to **7%** [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_special_election,_2017)[[^]](https://en.wikipedia.org/wiki/2017_Kansas%27s_4th_congressional_district_special_election)[[^]](https://time.com/4736025/trump-kansas-special-election-tweet/). This close outcome was largely influenced by significant national anti-Trump sentiment and local dissatisfaction with then-Governor Sam Brownback [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_special_election,_2017)[[^]](https://news.gallup.com/poll/224717/american-public-2017-learned.aspx)[[^]](https://prospect.org/2018/01/02/2017-year-reaction-resistance/)[[^]](https://www.wfae.org/2017-04-11/gop-holds-kansas-house-seat-as-democrats-surprise-upset-bid-falls-short)[[^]](https://en.wikipedia.org/wiki/2017_Kansas%27s_4th_congressional_district_special_election). Conversely, the upcoming 2026 general election is projected to be a much more straightforward win for incumbent Republican Ron Estes, reflecting the district's return to its reliably Republican voting patterns [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_special_election,_2017)[[^]](https://news.gallup.com/poll/224717/american-public-2017-learned.aspx)[[^]](https://prospect.org/2018/01/02/2017-year-reaction-resistance/)[[^]](https://www.wfae.org/2017-04-11/gop-holds-kansas-house-seat-as-democrats-surprise-upset-bid-falls-short)[[^]](https://en.wikipedia.org/wiki/2017_Kansas%27s_4th_congressional_district_special_election)[[^]](https://time.com/4736025/trump-kansas-special-election-tweet/)[[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner)[[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026).

Incumbent Ron Estes is favored for a decisive 2026 re-election. For the 2026 general election, Estes is seeking re-election in a district rated as "Solid R" or "Safe Republican," boasting an R+12 Cook Partisan Voting Index [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026)[[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026_(August_4_Republican_primary))[[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner). Although a pessimistic national mood is anticipated for 2026, these broader factors are not expected to make the race competitive in this specific district [[^]](https://news.gallup.com/poll/700448/americans-predict-challenging-2026-across-dimensions.aspx)[[^]](https://iop.harvard.edu/youth-poll/52nd-edition-spring-2026)[[^]](https://www.morganstanley.com/insights/articles/investor-guide-political-trends-2026)[[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner). Estes has consistently secured large general election victories, and prediction markets indicate a high **probability** of him winning by 17 points or more, suggesting that any significant electoral challenge is more likely to emerge from the Republican primary rather than the general election [[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner)[[^]](https://kalshi.com/markets/kxmidtermmov/kxmidtermmov-ks04r).

## What type of candidate profile or political event before the June 1, 2026 filing deadline could plausibly shift the expected margin?

Cook Partisan Voting Index (PVI) | R+12 or R+14 [[^]](https://en.wikipedia.org/wiki/Kansas%27s_4th_congressional_district)[[^]](https://grokipedia.com/page/Kansas's_4th_congressional_district)[[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026_(August_4_Democratic_primary)) |
2017 Special Election Margin | 6.2% [[^]](https://en.wikipedia.org/wiki/Kansas%27s_4th_congressional_district)[[^]](https://time.com/4736025/trump-kansas-special-election-tweet/) |
Third-Party Candidate Vote Share | Under 7% [[^]](https://grokipedia.com/page/Kansas's_4th_congressional_district) |

**Kansas's 4th District is strongly Republican, but margins can shift**

Kansas's 4th District is strongly Republican, but margins can shift. The district is characterized by a Cook Partisan Voting Index (PVI) ranging from R+12 to R+14, indicating a strong Republican advantage [[^]](https://en.wikipedia.org/wiki/Kansas%27s_4th_congressional_district)[[^]](https://grokipedia.com/page/Kansas's_4th_congressional_district)[[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026_(August_4_Democratic_primary)). The incumbent Republican U.S. Representative, Ron Estes, has consistently secured victories by substantial margins since 2017 [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District)[[^]](https://en.wikipedia.org/wiki/Kansas%27s_4th_congressional_district)[[^]](https://en.wikipedia.org/wiki/Ron_Estes)[[^]](https://grokipedia.com/page/Kansas's_4th_congressional_district). However, the 2017 special election provided evidence that a strong Democratic challenger could narrow the margin of victory, reducing it to **6.2%** [[^]](https://en.wikipedia.org/wiki/Kansas%27s_4th_congressional_district)[[^]](https://time.com/4736025/trump-kansas-special-election-tweet/).

Several factors could plausibly shift the expected margin of victory in the district. These include the emergence of a particularly strong challenger or a significant local economic downturn, especially one impacting Wichita's critical aerospace industry. A highly polarizing local social issue that becomes a central theme of the election could also alter voter behavior. Furthermore, a prominent third-party candidacy by a well-known local figure, presenting a resonant platform, could draw votes from the major parties and thus shift the expected margin, despite third-party candidates historically receiving minimal support, generally under **7%** of the vote in the district [[^]](https://grokipedia.com/page/Kansas's_4th_congressional_district).

## What do voter registration and demographic trends in Sedgwick County since 2020 suggest about the district's political trajectory?

2020 Sedgwick Co. Republican Voters | 121,255 [[^]](https://www.sedgwickcounty.org/media/57518/official-election-summary.pdf) |
May 2024 Sedgwick Co. Republican Voters | 133,606 [[^]](https://sos.ks.gov/elections/24elec/2024-05-01-Voter-Registration-Numbers-by-County.pdf) |
KS-04 Cook Partisan Voter Index (2024) | R+14 [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District)[[^]](https://www.ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2024) |

**Sedgwick County exhibits a sustained Republican voter registration advantage from 2020 to 2024**

Sedgwick County exhibits a sustained Republican voter registration advantage from 2020 to 2024. In 2020, registered voters totaled 304,190, comprising 121,255 Republicans and 80,392 Democrats [[^]](https://www.sedgwickcounty.org/media/57518/official-election-summary.pdf). By May 2024, the total registered voters increased to 335,381, with Republican registration reaching 133,606 and Democratic registration at 85,172 [[^]](https://sos.ks.gov/elections/24elec/2024-05-01-Voter-Registration-Numbers-by-County.pdf). This period saw Republican growth outpace Democratic growth, solidifying the GOP's stronghold in the county.

Sedgwick County's demographics and election outcomes consistently favor the Republican Party. The 2020 Census data indicates the county is **80.6%** White, with **16.7%** Hispanic/Latino residents, and **16.3%** of the population aged 65 or older [[^]](https://www.sedgwickcounty.org/about-sedgwick-county/demographics/)[[^]](https://www.census.gov/quickfacts/fact/table/sedgwickcountykansas/PST045224). This demographic profile typically supports the Republican advantage seen in many Kansas House districts. Election results for the Kansas 4th District reinforce this trend, with Ron Estes consistently securing high vote shares: **63.7%** in 2020, **63.3%** in 2022, and **65.2%** in 2024 [[^]](http://www.ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2020)[[^]](https://upgrade.ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2022)[[^]](https://www.augustachronicle.com/elections/results/2024-11-05/kansas/us-house). The district's 2024 Cook Partisan Voter Index of R+14 further aligns with these strong Republican margins [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District)[[^]](https://www.ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2024).

## How do non-partisan forecasters like the Cook Political Report and Sabato's Crystal Ball justify their 'Solid Republican' ratings for this district?

District Rating | Solid Republican or Safe Republican (Cook Political Report, Sabato's Crystal Ball) [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2024)[[^]](https://ballotpedia.org/Kentucky%27s_4th_Congressional_District_election,_2026_(May_19_Democratic_primary))[[^]](https://ballotpedia.org/Texas%27_32nd_Congressional_District_election,_2026_(March_3_Republican_primary)) |
Partisan Lean | R+12 or R+14 (approximately 12 to 14 percentage points more Republican than the national average) [[^]](https://grokipedia.com/page/Kansas's_4th_congressional_district)[[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026_(August_4_Republican_primary)) |
2024 Congressional Election Result | Incumbent Ron Estes re-elected with 65.0% of the vote [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2024) |

**Kansas's 4th District consistently receives a "Solid Republican" rating from forecasters**

Kansas's 4th District consistently receives a "Solid Republican" rating from forecasters. Non-partisan forecasters, including the Cook Political Report and Sabato's Crystal Ball, consistently classify Kansas's 4th Congressional District as "Solid Republican" or "Safe Republican" [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2024)[[^]](https://ballotpedia.org/Kentucky%27s_4th_Congressional_District_election,_2026_(May_19_Democratic_primary))[[^]](https://ballotpedia.org/Texas%27_32nd_Congressional_District_election,_2026_(March_3_Republican_primary)). This rating is justified by the district's strong historical Republican performance, a significant Republican advantage in voter registration, and its inherently conservative political leanings [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2024)[[^]](https://ballotpedia.org/Kentucky%27s_4th_Congressional_District_election,_2026_(May_19_Democratic_primary))[[^]](https://ballotpedia.org/Texas%27_32nd_Congressional_District_election,_2026_(March_3_Republican_primary)). The district's partisan lean is calculated at R+12 or R+14, indicating it votes approximately 12 to 14 percentage points more Republican than the national average in presidential elections [[^]](https://grokipedia.com/page/Kansas's_4th_congressional_district)[[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026_(August_4_Republican_primary)).

Strong Republican performance is evident in consistent electoral victories and voter demographics. The district has a long history of electing Republican representatives, with only one exception in the last half-century [[^]](https://en.wikipedia.org/wiki/Kansas%27s_4th_congressional_district). Republican candidates routinely win by substantial margins; for instance, incumbent Ron Estes was re-elected in the 2024 cycle with **65.0%** of the vote, following the Republican candidate securing **63.3%** in 2022 [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2024). Presidential election results further underscore this trend, with Donald Trump winning the district with **59.7%** of the vote in 2020 (post-redistricting) and by a 27-point margin in 2016 [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2024)[[^]](https://en.wikipedia.org/wiki/2017_Kansas%27s_4th_congressional_district_special_election). The voter base, primarily centered around Wichita and extending into rural and suburban areas, generally reflects conservative values, supported by a significant 2-to-1 Republican advantage in voter registration observed as recently as a 2017 special election [[^]](https://en.wikipedia.org/wiki/Kansas%27s_4th_congressional_district)[[^]](https://grokipedia.com/page/Kansas's_4th_congressional_district)[[^]](https://en.wikipedia.org/wiki/2017_Kansas%27s_4th_congressional_district_special_election).

## What Could Change the Odds

**Prediction markets indicate a strong likelihood of a Republican victory in Kansas's 4th Congressional District.** Polymarket shows the "Republican Party" at **85%** (and ~86.5–**87%** in a localized French snippet) to win the KS-04 House Election [[^]](https://polymarket.com/event/ks-04-house-election-winner/will-the-republican-party-win-the-ks-04-house-seat)[[^]](https://polymarket.com/fr/event/ks-04-house-election-winner). Kalshi's "midterm margin of victory" **market** shows Republicans are favored with a large-win distribution, with Octagon AI stating Republicans’ bucket is 11+ points at **89%** versus approximately **90%** **market** [[^]](https://kalshi.com/markets/kxmidtermmov/midterm-margin-of-victory/kxmidtermmov-ks04r). The district has a Cook Partisan Voter Index of R+12 heading into 2026 [[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026), and Cook Political Report describes the seat as assured/secure for the incumbent [[^]](https://www.cookpolitical.com/house/race/483121). Incumbent Ron Estes (R) filed for reelection in January 2026 [[^]](https://www.kwch.com/2026/01/28/rep-ron-estes-files-reelection/).

**Significant events that could impact market probabilities include the filing deadline and the primary election.** The filing deadline for candidates is June 1, 2026 [[^]](https://www.cookpolitical.com/house/race/483121). The primary election, scheduled for August 4, 2026, is noted as the period with the highest volatility risk as the nominee question is decided [[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner)[[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026)[[^]](https://www.cookpolitical.com/house/race/483121). The general election contract resolves on November 3, 2026 [[^]](https://www.lines.com/prediction-markets/elections/ks-04-house-election-winner)[[^]](https://ballotpedia.org/Kansas%27_4th_Congressional_District_election,_2026).

## Key Dates & Catalysts

- **Expiration:** November 03, 2027
- **Closes:** November 03, 2027

## Decision-Flipping Events

- Prediction markets indicate a strong likelihood of a Republican victory in Kansas's 4th Congressional District.
- Polymarket shows the "Republican Party" at **85%** (and ~86.5–**87%** in a localized French snippet) to win the KS-04 House Election [^] [^] .
- Kalshi's "midterm margin of victory" **market** shows Republicans are favored with a large-win distribution, with Octagon AI stating Republicans’ bucket is 11+ points at **89%** versus approximately **90%** **market** [^] .
- The district has a Cook Partisan Voter Index of R+12 heading into 2026 [^] , and Cook Political Report describes the seat as assured/secure for the incumbent [^] .

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## Historical Resolutions

No historical resolution data available for this series.

## Disclaimer

This content is for informational and educational purposes only and does not constitute financial, investment, legal, or trading advice.
Prediction markets involve risk of loss. Past performance does not guarantee future results.
We are not affiliated with Kalshi or any prediction market platform. Market data may be delayed or incomplete.

### Data Sources & Model Transparency

**Data Sources:** Octagon Deep Research aggregates information from multiple sources including news, filings, and market data.

**Freshness:** Analysis is generated periodically and may not reflect the latest developments. Verify critical information from primary sources.

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