# Pennsylvania's 8th District margin of victory

Pennsylvania's 8th District

Updated: May 8, 2026

Category: Elections

HTML: /markets/elections/pennsylvania-s-8th-district-margin-of-victory/

## Short Answer

**Key takeaway.** The **model** sees potential mispricing for Republicans winning Pennsylvania's 8th District by 1+ pts at **25.9%** **model** vs **0.0%** **market**, suggesting a reduced margin or potential Democratic win due to shifting ratings and negative attention on the Republican candidate.

## Key Claims (January 2026)

**- - Cook Political Report shifted the district rating to "Toss-up."
- Negative attention on Bresnahan's stock trading affects his election outlook.** - No non-partisan polling data is currently available for the matchup.
- A Q3 2026 fundraising comparison for candidates is not currently possible.
- Bresnahan (R) secured a 1.6-point victory margin in the 2024 election.
- President Biden's approval rating could influence voter turnout in this district.

### 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** forecasts **25.9%** **probability** for PA-08 vs 0c **market**, a +25.9pp gap driven by Bresnahan's trading issues.

### Who Wins and Why

| Outcome | Market | Model | Why |
| --- | --- | --- | --- |
| Republicans, 7+ pts | 12.0% | 7.0% | Cook Political Report's 'Toss-up' rating and Bresnahan Jr.'s stock issues suggest a reduced Republican margin. |
| Republicans, 4+ pts | 18.0% | 10.5% | Cook Political Report's 'Toss-up' rating and Bresnahan Jr.'s stock issues suggest a tighter Republican victory. |
| Republicans, 1+ pts | 0.0% | 25.9% | Cook Political Report's 'Toss-up' rating indicates a very close potential Republican victory. |

## Model vs Market

| Outcome | Market Probability | Octagon Model Probability |
| --- | --- | --- |
| Republicans, 7+ pts | 12.0% | 7.0% |
| Republicans, 4+ pts | 18.0% | 10.5% |
| Republicans, 1+ pts | 0.0% | 25.9% |
| Republicans, 10+ pts | 0.0% | 1.0% |

- Expiration: November 3, 2027

## Market Behavior & Price Dynamics

This prediction market shows a dramatic upward trend, starting at a 1.0% probability and currently holding at 38.0%. The most significant price movement is a 35.0 percentage point spike on May 05, 2026, which took the price from 1.0% to 36.0%. The provided context does not offer a specific news event, social media activity, or other market factor that would explain this sharp increase in perceived probability. The price has since stabilized at 38.0%, suggesting this is the new baseline for market expectations, though it is a very new level.

A critical factor in this market is the complete lack of trading activity, with a total volume of zero contracts traded across all data points. This indicates that the price movements, including the major spike, are not the result of buying and selling pressure from market participants. Instead, the price may be determined by an automated market maker or by unfilled offers. The absence of volume suggests there is no market conviction behind the current 38.0% price.

The chart suggests a rapid and significant shift in sentiment toward a higher probability of the outcome. However, this sentiment is not validated by any trading volume, making the price's reliability as a forecast questionable. The price has established a new plateau at 38.0% after its initial low of 1.0%, but without trading activity, it's difficult to determine if this level represents true support or simply the market's most recent resting point in an illiquid environment.

## Significant Price Movements

### Outcome: Republicans, 4+ pts

#### 📉 May 07, 2026: 9.0pp drop

Price decreased from 27.0% to 18.0%

**What happened:** The primary driver of the 9.0 percentage point drop on May 07, 2026, appears to be a traditional news report indicating a strengthening Democratic position. A Pennsylvania Capital-Star article, published on the same day, reported that Democrats began expanding their statewide voter registration advantage for the first time in years, discussing how this trend affects competitive districts like PA-08 [[^]](https://penncapital-star.com/commentary/pennsylvania-voter-registration-democrats-expand-advantage-for-the-first-time-in-years/)[[^]](https://www.yahoo.com/news/articles/pennsylvania-voter-registration-democrats-expand-074237788.html). While this report did not quantify a 9.0 percentage point drop for PA-08 specifically, it coincided with the market movement and highlighted a broader shift in voter dynamics unfavorable to Republicans. Social media was irrelevant as no related activity or viral narratives were identified in the provided information for this period.

### Outcome: Republicans, 1+ pts

#### 📈 May 05, 2026: 35.0pp spike

Price increased from 1.0% to 36.0%

**What happened:** The provided web research lacks specific information regarding social media activity, news, or market factors on or around May 05, 2026, that could explain the 35.0 percentage point price spike. Although incumbent Rob Bresnahan's stock trades are mentioned as a potential Democratic line of attack, this context is not tied to a specific dated event around the market movement [[^]](https://www.cookpolitical.com/house/race/483946). Therefore, based on the available data, the primary driver for this price movement cannot be identified. Social media's role in this specific event is irrelevant due to the absence of relevant temporal data.

## Contract Snapshot

A "Yes" resolution occurs if the Republican Party wins the 2026 U.S. House of Representatives election in Pennsylvania's 8th District by 1 percentage point or more. A "No" resolution occurs if the Republican Party wins by less than 1 percentage point, ties, or loses, with the margin calculated as the Republican Party's vote percentage minus the vote percentage of the candidate/party immediately behind them.

The market opened on May 5, 2026, and will close and expire early if certified election results are published, otherwise by November 3, 2027. Official results will be verified from the election authority responsible for certifying results, linked via nass.org/can-I-vote.

## Market Discussion

The margin of victory for Pennsylvania's 8th District has fluctuated, with Democrat Matt Cartwright winning by 2.44 percentage points in 2022 and 4 points in 2020, following a 9.2-point victory in 2018 [[^]](https://elections2024.thehill.com/forecast/2024/house/pennsylvania-8/). Non-partisan election forecasters commonly rate the district as "lean" or "tilt" Republican for 2026, with The Cook Political Report specifically rating it "Lean R" as of April 7, 2026 [[^]](https://whyy.org/articles/2026-elections-united-states-house-pennsylvania/). Prediction markets as of May 5, 2026, show varying probabilities for both Democratic and Republican margins of victory [[^]](https://kalshi.com/markets/kxmidtermmov/kxmidtermmov-pa08d).

## Market Data

| Contract | Yes Bid | Yes Ask | Last Price | Volume | Open Interest |
| --- | --- | --- | --- | --- | --- |
| Republicans, 1+ pts | 38% | 39% | 0% | $0 | $0 |
| Republicans, 10+ pts | 10% | 11% | 0% | $0 | $0 |
| Republicans, 4+ pts | 18% | 19% | 18% | $3,824 | $599 |
| Republicans, 7+ pts | 12% | 13% | 12% | $4,005 | $453 |

## How do Rob Bresnahan Jr.'s and Paige Cognetti's Q3 2026 fundraising totals and cash-on-hand compare?

Rob Bresnahan Jr. Q1 2026 Cash-on-hand | $2,214,132.25 (as of 03/31/2026) [[^]](https://www.fec.gov/data/candidate/H4PA08124/) |
Paige Cognetti Q1 2026 Cash-on-hand | $1,924,859.07 (as of 03/31/2026) [[^]](https://www.fec.gov/data/candidate/H6PA08293/) |
Q3 2026 Fundraising Data | Not available [[^]](https://www.fec.gov/data/candidate/H4PA08124/)[[^]](https://www.fec.gov/data/candidate/H6PA08293/) |

**A direct comparison of Q3 2026 fundraising totals is currently not possible**

A direct comparison of Q3 2026 fundraising totals is currently not possible. As of May 8, 2026, an accurate comparison of Rob Bresnahan Jr.'s and Paige Cognetti's Q3 2026 fundraising totals and cash-on-hand cannot be made. This is because only financial figures up to Q1 2026 are presently available, rather than the requested data for Q3 2026 [[^]](https://www.fec.gov/data/candidate/H4PA08124/)[[^]](https://www.fec.gov/data/candidate/H6PA08293/).

Available data provides insight into each candidate's Q1 2026 finances. Rob Bresnahan Jr.'s cash-on-hand is reported as **$2,214,132.25**, covering the period from January 1, 2025, to March 31, 2026, which concludes Q1 2026 [[^]](https://www.fec.gov/data/candidate/H4PA08124/). For Paige Cognetti, her cash-on-hand is recorded at **$1,924,859.07**, for the period from September 2, 2025, to March 31, 2026, also ending in Q1 2026 [[^]](https://www.fec.gov/data/candidate/H6PA08293/). Consequently, the lack of Q3 2026 financial data prevents a comprehensive assessment of their fundraising activities and cash reserves for that particular quarter based on currently accessible information [[^]](https://www.fec.gov/data/candidate/H4PA08124/)[[^]](https://www.fec.gov/data/candidate/H6PA08293/).

## What evidence from historical voting patterns supports the Cook Political Report's 'Lean R' rating for Pennsylvania's 8th District?

Cook Partisan Voting Index (PVI) | R+4 [[^]](https://ballotpedia.org/Pennsylvania%27s_8th_Congressional_District_election,_2026_(May_19_Republican_primary)) |
Presidential Election Wins | Donald Trump in 2016, 2020, and 2024 [[^]](https://en.wikipedia.org/wiki/Pennsylvania%27s_8th_congressional_district) |
PVI significance | 4 percentage points more Republican than national average [[^]](https://ballotpedia.org/Pennsylvania%27s_8th_Congressional_District_election,_2026_(May_19_Republican_primary)) |

**Pennsylvania's 8th District was initially rated 'Lean R' due to its partisan lean**

Pennsylvania's 8th District was initially rated 'Lean R' due to its partisan lean. The Cook Political Report's initial 'Lean R' rating for Pennsylvania's 8th District was primarily supported by its Cook Partisan Voting Index (PVI) of R+4 [[^]](https://ballotpedia.org/Pennsylvania%27s_8th_Congressional_District_election,_2026_(May_19_Republican_primary)). This PVI indicates the district voted 4 percentage points more Republican than the national average in the 2020 and 2024 presidential elections, serving as a key measure of its inherent partisan lean [[^]](https://ballotpedia.org/Pennsylvania%27s_8th_Congressional_District_election,_2026_(May_19_Republican_primary))[[^]](https://en.wikipedia.org/wiki/Cook_Partisan_Voting_Index). Further solidifying this assessment, Donald Trump consistently won the district in the 2016, 2020, and 2024 presidential elections [[^]](https://en.wikipedia.org/wiki/Pennsylvania%27s_8th_congressional_district).

Despite its Republican lean, the district historically elected a Democrat. Despite the district's strong Republican lean in presidential contests, it was notably represented by Democrat Matt Cartwright for an extended period [[^]](https://en.wikipedia.org/wiki/Pennsylvania%27s_8th_congressional_district). At one point, it was recognized as the most Republican-leaning district held by a member of the Congressional Progressive Caucus [[^]](https://en.wikipedia.org/wiki/Pennsylvania%27s_8th_congressional_district). While the Cook Political Report later adjusted its rating for PA-08 from 'Lean R' to 'Toss-up' in April 2026, citing a narrow victory and a bipartisan stance, the initial 'Lean R' assessment was firmly rooted in these historical voting patterns and the R+4 PVI [[^]](https://dccc.org/cook-political-five-more-house-ratings-shift-toward-democrats/)[[^]](https://www.washingtonexaminer.com/news/campaigns/4519629/five-gop-house-seats-shift-toward-democrats-cook-political-report/)[[^]](https://ballotpedia.org/Pennsylvania%27s_8th_Congressional_District_election,_2026_(May_19_Republican_primary))[[^]](https://en.wikipedia.org/wiki/Pennsylvania%27s_8th_congressional_district).

## How might the national political environment, particularly President Biden's approval rating, influence voter turnout in this R+4 district during the 2026 midterms?

Biden Approval Rating Impact | An input for House 'fundamentals' that can influence voter turnout and enthusiasm [[^]](https://fivethirtyeight.com/features/biden-is-very-unpopular-it-may-not-tell-us-much-about-the-midterms/) |
PA-08 Cook PVI | R+4 (about 4 percentage points more Republican than the national average) [[^]](https://ballotpedia.org/Pennsylvania%27s_8th_Congressional_District_election,_2026)[[^]](https://ballotpedia.org/Pennsylvania's_8th_Congressional_District_election,_2026) |
2022 Midterm Outcome | Anticipated large 'red wave' did not materialize nationwide despite low Biden approval [[^]](https://news.gallup.com/poll/406421/biden-congress-job-ratings-unchanged-midterm-elections.aspx) |

**Biden's approval influences turnout but may not overcome district's lean**

Biden's approval influences turnout but may not overcome district's lean. President Biden's approval rating is considered a factor in House 'fundamentals,' suggesting it could influence voter turnout and enthusiasm, even in districts with an inherent partisan lean [[^]](https://fivethirtyeight.com/features/biden-is-very-unpopular-it-may-not-tell-us-much-about-the-midterms/). However, Pennsylvania's 8th Congressional District has a Cook PVI of R+4, indicating it is approximately four percentage points more Republican than the national average. This underlying partisan tilt implies that shifts in Biden's approval rating are unlikely to entirely overcome the district's fundamental partisan lean [[^]](https://ballotpedia.org/Pennsylvania%27s_8th_Congressional_District_election,_2026)[[^]](https://ballotpedia.org/Pennsylvania's_8th_Congressional_District_election,_2026).

Local dynamics can weaken presidential approval's impact on turnout. The connection between presidential approval and turnout in specific districts can be diminished or superseded by local political dynamics. According to FiveThirtyEight, fundamentals based on approval ratings may not hold if voters distinguish between their preferences for the president and their congressional representatives, or as new information becomes available [[^]](https://fivethirtyeight.com/features/biden-is-very-unpopular-it-may-not-tell-us-much-about-the-midterms/). This perspective is supported by the 2022 midterms, where Gallup reported that despite President Biden's relatively low approval, the anticipated 'red wave' nationwide did not materialize, suggesting that low presidential approval does not automatically lead to significantly lower Democratic participation or greater Republican turnout gains across the country [[^]](https://news.gallup.com/poll/406421/biden-congress-job-ratings-unchanged-midterm-elections.aspx).

National conditions still influence margin of victory in close races. Nonetheless, national conditions, including the enthusiasm driven by presidential approval, are recognized as factors that can affect the margin of victory in Pennsylvania's 8th District for 2026 once a race becomes sufficiently close and sensitive to turnout [[^]](https://kalshi.com/markets/kxmidtermmov/kxmidtermmov-pa08r)[[^]](https://polymarket.com/event/pa-08-house-election-winner). This ongoing potential impact is evident from the active trading and updates related to the seat on various prediction **market** sites [[^]](https://kalshi.com/markets/kxmidtermmov/kxmidtermmov-pa08r)[[^]](https://polymarket.com/event/pa-08-house-election-winner).

## What recent, publicly available polling data for the 2026 Bresnahan vs. Cognetti matchup has been released by non-partisan pollsters?

Non-partisan polling | No publicly available data found for 2026 Bresnahan vs. Cognetti matchup [[^]](https://www.thehousemajoritypac.com/news/new-hmp-polling-shows-rob-bresnahan-trailing-paige-cognetti-in-pa-08) |
Paige Cognetti vote share | 45% (House Majority PAC) [[^]](https://www.thehousemajoritypac.com/news/new-hmp-polling-shows-rob-bresnahan-trailing-paige-cognetti-in-pa-08) |
Rob Bresnahan vote share | 43% (House Majority PAC) [[^]](https://www.thehousemajoritypac.com/news/new-hmp-polling-shows-rob-bresnahan-trailing-paige-cognetti-in-pa-08) |

**No non-partisan polling data is currently available for this matchup**

No non-partisan polling data is currently available for this matchup. As of the latest research, no publicly available polling data for the potential 2026 Bresnahan vs. Cognetti matchup in PA-08 has been released by non-partisan pollsters. Searches to locate such information regarding this recent 2026 PA-08 contest were unsuccessful [[^]](https://www.thehousemajoritypac.com/news/new-hmp-polling-shows-rob-bresnahan-trailing-paige-cognetti-in-pa-08).

A partisan poll indicates a narrow lead for Cognetti over Bresnahan. The only publicly available head-to-head vote-share polling that could be directly verified comes from the partisan House Majority PAC. According to this specific poll, Paige Cognetti received **45%** of the vote share, while Rob Bresnahan garnered **43%** [[^]](https://www.thehousemajoritypac.com/news/new-hmp-polling-shows-rob-bresnahan-trailing-paige-cognetti-in-pa-08).

## To what extent could criticism of Rob Bresnahan Jr.'s stock trading activities affect his polling numbers among independent voters before November 2026?

Concerned Voters | 54% had "very serious concerns" about trades (partisan memo) [[^]](https://dccc.org/memo-rob-bresnahan-has-deeply-damaged-his-own-re-election-odds-with-his-prolific-stock-trading-2/) |
Total Trade Value | $7.24M this year (as of Aug 2025) [[^]](https://www.inquirer.com/politics/pennsylvania/congressional-stock-trading-ban-pennsylvania-rob-bresnahan-20250810.html) |
Cook Political Report Rating | PA-08 moved from "Lean Republican" to "Toss Up" for 2026 general election [[^]](https://www.cookpolitical.com/house/race/483946) |

**Criticism of Rob Bresnahan Jr.'s stock trading significantly impacts his election outlook**

Criticism of Rob Bresnahan Jr.'s stock trading significantly impacts his election outlook. This issue is identified as a major factor influencing the 2026 general election, with a partisan memo indicating that **54%** of voters hold "very serious concerns" regarding these activities [[^]](https://dccc.org/memo-rob-bresnahan-has-deeply-damaged-his-own-re-election-odds-with-his-prolific-stock-trading-2/). The controversy has generated doubts about Bresnahan's ability to win a key swing district, as Republicans are concerned it could alienate essential voters [[^]](https://www.inquirer.com/politics/pennsylvania/congressional-stock-trading-ban-pennsylvania-rob-bresnahan-20250810.html).

Bresnahan's extensive trading directly led to a crucial election rating change. As of August 2025, reports detail Bresnahan engaging in 617 trades amounting to **$7.24** million "this year" [[^]](https://www.inquirer.com/politics/pennsylvania/congressional-stock-trading-ban-pennsylvania-rob-bresnahan-20250810.html). The Cook Political Report explicitly cited this stock trading issue as the reason for reclassifying the PA-08 2026 general election rating from "Lean Republican" to "Toss Up," noting that the issue has "dogged him all cycle" [[^]](https://www.cookpolitical.com/house/race/483946). While the specific impact of these activities on independent voters remains unquantified in the available sources, the broader implications are clear [[^]](https://www.cookpolitical.com/house/race/483946).

Prediction markets currently indicate a highly competitive and tight race. For instance, Polymarket's PA-08 "House Election Winner" **market**, which will resolve around November 4, 2026, presently shows the Democratic Party with a leading **probability** [[^]](https://polymarket.com/event/pa-08-house-election-winner). This reflects that the **market** is already factoring in a very close contest. Kalshi also offers a PA-08 "margin of victory" contract, though specific pricing or an issue-specific polling **model** for this **market** is not provided in the research [[^]](https://kalshi.com/markets/kxmidtermmov/kxmidtermmov-pa08r).

## What Could Change the Odds

**The Polymarket "PA-08 House Election Winner" market currently prices the Democratic Party at ~56% and the Republican Party at ~45% [[^]](https://worldcoin.polymarket.com/event/pa-08-house-election-winner).** This dynamic follows the 2024 general election where Bresnahan (R) secured a 1.6-point margin of victory with **50.8%** of the vote against Cartwright (D)'s **49.2%** [[^]](https://ballotpedia.org/Pennsylvania%27s_8th_Congressional_District_election,_2024)[[^]](https://www.washingtonpost.com/elections/results/2024/11/05/pennsylvania-house-district-8/). Key dates for the 2026 election cycle include the primary on May 19, 2026, and the general election on November 3, 2026 [[^]](https://www.ballotpedia.org/Pennsylvania%27s_8th_Congressional_District)[[^]](https://www.pa.gov/agencies/vote/elections/upcoming-elections)[[^]](https://ballotpedia.org/Pennsylvania's_8th_Congressional_District_election,_2026).

**Market-relevant catalysts include Q1 2026 fundraising results, which showed Cognetti outraised Bresnahan ($1.39M vs $715k), though Bresnahan still held a lead in cash on hand ($2.21M vs $1.92M) [[^]](https://www.standardspeaker.com/2026/04/16/cognetti-outraises-bresnahan-in-years-first-quarter-bresnahan-leads-in-cash-on-hand/).** Furthermore, negative attention surrounding Bresnahan’s stock trades has contributed to a Democratic attack line and led to the Cook Political Report moving the PA-08 congressional race to a "Toss-Up" [[^]](https://www.standardspeaker.com/2026/04/16/cognetti-outraises-bresnahan-in-years-first-quarter-bresnahan-leads-in-cash-on-hand/)[[^]](https://www.politicspa.com/cook-political-report-moves-pa-08-congressional-race-to-toss-up/146056/)[[^]](https://poconoreview.com/pa-8th-congressional-district-primary-2026-bresnahan-cognetti-unopposed/). The primary filing deadline was March 10, 2026, with the Republican primary scheduled for May 19, 2026, and Bresnahan and Cognetti described as the effective main candidates, indicating a potentially lower risk of primary disruption compared to more contested races [[^]](https://poconoreview.com/pa-8th-congressional-district-primary-2026-bresnahan-cognetti-unopposed/)[[^]](https://ballotpedia.org/Pennsylvania%27s_8th_Congressional_District_election,_2026_(May_19_Republican_primary)).

## Key Dates & Catalysts

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

## Decision-Flipping Events

- The Polymarket "PA-08 House Election Winner" **market** currently prices the Democratic Party at ~**56%** and the Republican Party at ~**45%** [^] .
- This dynamic follows the 2024 general election where Bresnahan (R) secured a 1.6-point margin of victory with **50.8%** of the vote against Cartwright (D)'s **49.2%** [^] [^] .
- Key dates for the 2026 election cycle include the primary on May 19, 2026, and the general election on November 3, 2026 [^] [^] [^] .
- **Market**-relevant catalysts include Q1 2026 fundraising results, which showed Cognetti outraised Bresnahan (**$1.39M** vs **$715**k), though Bresnahan still held a lead in cash on hand (**$2.21M** vs **$1.92M**) [^] .

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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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