# How many Republican senators will lose reelection in 2026?

2026 elections

Updated: April 29, 2026

Category: Elections

Tags: US Elections

HTML: /markets/elections/us-elections/how-many-republican-senators-will-lose-reelection-in-2026/

## Short Answer

**Key takeaway.** Both the **model** and the **market** expect exactly 4 Republican senators to lose reelection in 2026, with no compelling evidence of mispricing.

## Key Claims (January 2026)

**- - Senator Susan Collins faces low independent approval and high overall disapproval.** - DSCC made substantial ad reservations targeting Maine and North Carolina races.
- Senator Thom Tillis also shows signs of vulnerability in North Carolina.
- Senators Cassidy and Cornyn are well-funded incumbents in reliably Republican states.
- Current DSCC investment levels are lower than their successful 2022 campaigns.

### 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.** **Market**'s 3c for 0 losses slightly exceeds the **2.6%** **model**, as Senator Collins' vulnerability complicates this outcome.

### Who Wins and Why

| Outcome | Market | Model | Why |
| --- | --- | --- | --- |
| 5 or more | 22.0% | 22.9% | Model higher by 0.9pp |
| Exactly 4 | 41.0% | 38.8% | Market higher by 2.2pp |
| Exactly 0 | 3.0% | 2.6% | Market higher by 0.4pp |

## Model vs Market

| Outcome | Market Probability | Octagon Model Probability |
| --- | --- | --- |
| 5 or more | 22.0% | 22.9% |
| Exactly 4 | 41.0% | 38.8% |
| Exactly 0 | 3.0% | 2.6% |
| Exactly 2 | 6.5% | 8.6% |
| Exactly 3 | 16.0% | 14.9% |
| Exactly 1 | 8.0% | 12.1% |

- Expiration: December 31, 2026

## Market Behavior & Price Dynamics

This market, which predicts the number of Republican senators who will lose their reelection bids in 2026, exhibits a complete lack of price action. The price has remained static at a 3.0% probability since its inception, indicating a flat, sideways trend with no significant movements, spikes, or drops. Because the market is predicting a numerical outcome, the 3.0% price can be interpreted as an expected value of 0.03 senators losing. The absence of any price changes means there are no specific events or news developments reflected in the chart.

The most significant feature of this market is the total trading volume of zero contracts. This indicates a complete lack of participation from traders. Without any trading activity, the current price is merely the opening proposition set by the market creator and does not reflect any collective sentiment or conviction from a broader audience. The absence of volume means that no support or resistance levels have been established, as the initial price has never been tested by buying or selling pressure.

Overall, the chart suggests an inactive and illiquid market. The sentiment reflected by the 3.0% price is singular—likely that of the market creator—and posits a very low probability of any Republican incumbents losing in the 2026 cycle. However, this sentiment has not been validated, challenged, or confirmed by any trading activity, rendering the current price purely theoretical at this stage. The market is effectively dormant, awaiting trader engagement to establish a true consensus.

## Contract Snapshot

This market resolves to YES if exactly 4 Republican senators actively seeking re-election lose their bids (including primaries, general elections, runoffs, retention elections, or recalls) in 2026; otherwise, it resolves to NO. Retirements, withdrawals, deaths, resignations, disqualifications, or winning as an independent after a primary loss do not count as losses. The market opens September 16, 2025, and will close early if all relevant 2026 elections are completed and certified, otherwise by December 31, 2026, at 10:00 AM EST, with payouts 30 minutes after closing.

## Market Discussion

The market currently favors exactly four Republican senators losing reelection in 2026 (41%), though significant support also exists for "5 or more" (22%) and "Exactly 3" (16%). Traders are debating the vulnerability of specific senators, including Cornyn (Texas), Collins (Maine), Cassidy (Louisiana), Husted (Ohio), and Sullivan (Alaska). The possibility of Senator Cornyn being "yoinked" in his primary or general election is a recurring point of contention, with some anticipating a broader "wrecking" for Republicans.

## Market Data

| Contract | Yes Bid | Yes Ask | Last Price | Volume | Open Interest |
| --- | --- | --- | --- | --- | --- |
| Exactly 0 | 2% | 4.3% | 3% | $5,044 | $1,706 |
| Exactly 1 | 8% | 8.9% | 8% | $4,375 | $2,937 |
| Exactly 2 | 6.6% | 14% | 6.5% | $4,677 | $2,667 |
| Exactly 3 | 16% | 17% | 16% | $4,425 | $3,453 |
| Exactly 4 | 33% | 34% | 41% | $9,405.99 | $5,836.99 |
| 5 or more | 22% | 23% | 22% | $12,284.15 | $6,710.81 |

## What were Senators Collins' and Tillis' independent approval ratings in Q2 2025?

Sen. Collins Independent Approval (June 2025) | 32 percent [[^]](https://www.themainewire.com/2025/07/susan-collins-approval-rating-at-record-low-poll-claims/) |
Sen. Collins Overall Approval (Q2 2025) | 43% [[^]](https://pro.morningconsult.com/analysis/susan-collins-maine-approval-rating) |
Sen. Tillis Independent Approval (Jan 2025) | 45 percent [[^]](https://yellowhammernews.com/wp-content/uploads/2025/01/Senator-Approval-Outlook-January-2025.pdf) |

**Senator Susan Collins’ independent approval rating stood at 32 percent in June 2025**

Senator Susan Collins’ independent approval rating stood at 32 percent in June 2025. Senator Collins of Maine recorded this 32 percent approval rating among registered Independents, according to a University of New Hampshire Survey Center poll cited by The Maine Wire and Newsweek [[^]](https://www.themainewire.com/2025/07/susan-collins-approval-rating-at-record-low-poll-claims/). During Q2 2025, Morning Consult data indicated Collins' total approval among all Maine voters was 43 percent, with 51 percent disapproving [[^]](https://pro.morningconsult.com/analysis/susan-collins-maine-approval-rating). While a specific Q2 2025 independent approval percentage from Morning Consult was not explicitly provided, the data did show a 6 percentage point dip in her approval among Maine Independents from Q1 to Q2 2025, and a 17-point slide in her net approval among Independents from Q1 2021 to Q2 2025 [[^]](https://pro.morningconsult.com/analysis/susan-collins-maine-approval-rating).

Senator Thom Tillis lacks specific Q2 2025 independent approval ratings. For Senator Tillis of North Carolina, specific approval ratings among registered Independents for Q2 2025 from a reputable non-partisan pollster were not available in the provided research. The most recent data found for Tillis' independent approval was from January 2025 (Q1 2025), showing a 45 percent approval rating and 42 percent disapproval among Independents in North Carolina [[^]](https://yellowhammernews.com/wp-content/uploads/2025/01/Senator-Approval-Outlook-January-2025.pdf). Other sources referenced older overall approval data or focused on future election cycles without relevant Q2 2025 independent approval numbers [[^]](https://www.carolinajournal.com/new-poll-shows-mixed-opinions-on-trump-tillis-among-north-carolinians/).

## Did Trump-Endorsed Challengers Outraise Incumbent Senators Before 2026?

Senator Bill Cassidy Cash on Hand | $3.7 million (March 31, 2025) [[^]](https://www.wbrz.com/news/cassidy-letlow-and-fleming-have-millions-of-dollars-on-hand-heading-into-may-primary/) |
Julia Letlow Cash on Hand | $1.3 million (March 31, 2025) [[^]](https://www.wbrz.com/news/cassidy-letlow-and-fleming-have-millions-of-dollars-on-hand-heading-into-may-primary/) |
Senator John Cornyn Cash on Hand | $10.1 million (March 2026) [[^]](https://www.texastribune.org/2026/04/15/john-cornyn-ken-paxton-runoff-first-quarter-fundraising/) |

**No Trump-endorsed primary challengers for Senator Bill Cassidy (LA) or Senator John Cornyn (TX) reported higher cash on hand than the incumbent in any quarterly FEC filing prior to January 1, 2026**

No Trump-endorsed primary challengers for Senator Bill Cassidy (LA) or Senator John Cornyn (TX) reported higher cash on hand than the incumbent in any quarterly FEC filing prior to January 1, 2026. For Senator Bill Cassidy of Louisiana, his Trump-backed primary challenger, U.S. Rep. Julia Letlow [[^]](https://us.cnn.com/2026/01/20/politics/julia-letlow-bill-cassidy-louisiana-senate), reported **$1.3** million in cash on hand as of March 31, 2025. During the same period, Senator Cassidy reported a higher figure of **$3.7** million [[^]](https://www.wbrz.com/news/cassidy-letlow-and-fleming-have-millions-of-dollars-on-hand-heading-into-may-primary/). This data confirms that Letlow's reported cash on hand was less than that of Senator Cassidy.

Regarding Senator John Cornyn of Texas, no Trump-endorsed primary challengers were identified with a higher cash on hand figure before the January 1, 2026 deadline. While Ken Paxton is mentioned as a challenger, the available sources do not explicitly confirm a Trump endorsement against Senator Cornyn [[^]](https://www.texastribune.org/2026/04/15/john-cornyn-ken-paxton-runoff-first-quarter-fundraising/). Furthermore, the cash on hand figures provided for Senator Cornyn (**$10.1** million) and Paxton (**$2.3** million) are from March 2026 [[^]](https://www.texastribune.org/2026/04/15/john-cornyn-ken-paxton-runoff-first-quarter-fundraising/), which falls after the specified deadline for FEC filings, and no earlier comparative data was available.

## Can Voter Registration Changes in Key Counties Be Determined by Q1 2026?

Net Change Determinability | Cannot be fully determined (due to missing baseline data) [[^]](https://www.maine.gov/sos/elections-voting/voter-data) |
Nov 2024 Party Data | Absent for specific party figures in Cumberland (ME), Wake (NC), and Collin (TX) counties [[^]](https://www.maine.gov/sos/elections-voting/voter-data) |
Q1 2026 Data Source | Content of 'April 2026 Voter Registration by Party Updates' unconfirmed [[^]](https://www.captaink.us/p/april-2026-voter-registration-by) |

**The precise net change in voter registration remains unquantifiable at this time**

The precise net change in voter registration remains unquantifiable at this time. The net change in voter registration by party (Democrat vs. Republican) in Cumberland (ME), Wake (NC), and Collin (TX) counties from the November 2024 general election to Q1 2026 cannot be fully determined. This limitation primarily stems from the absence of specific voter registration data by party for the November 2024 baseline period for these counties, which is essential for calculating any net change.

Existing sources lack specific, time-bound registration data for a baseline. While general voter data portals are available for Maine [[^]](https://www.maine.gov/sos/elections-voting/voter-data), Wake County, North Carolina [[^]](https://www.wake.gov/departments-government/board-elections/data-reports/voter-registration-statistics), and Collin County, Texas [[^]](https://www.collincountytx.gov/elections/statistics), these sources do not explicitly provide the specific voter registration figures by party for November 2024 needed to establish a starting point for calculation. Some provided information discusses broader demographic trends, such as a North Carolina opinion piece on the voting gap [[^]](https://www.newsobserver.com/opinion/article314200404.html) or Collin County's population growth [[^]](https://collinchronicles.com/collin-countys-population-boom-fuels-surge-in-voter-registration-across-fast-growing-cities/), but these do not offer the granular, time-specific data requested for party registration numbers.

Future data for 2026 is noted but its content is currently inaccessible. One referenced source, titled 'April 2026 Voter Registration by Party Updates for Key 2026 and 2028 Battlegrounds' [[^]](https://www.captaink.us/p/april-2026-voter-registration-by), falls within the Q1 2026 timeframe. However, its specific content is not provided, making it impossible to confirm whether it covers the specified counties or offers a direct comparison to November 2024 figures. Without the definitive November 2024 registration numbers for Democrats and Republicans in these counties, calculating the net change by Q1 2026 is not feasible using the current information.

## How Does DSCC's 2026 Spending Compare to 2022 Senate Races?

DSCC 2026 Maine Ad Reservations | $3.5 million [[^]](https://bdn-data.s3.amazonaws.com/uploads/2026/03/maine_senate_ad_reservations_bdn_v3.html) |
DSCC 2026 North Carolina Ad Reservations | $5.0 million [[^]](https://uspollingdata.com/news/money-in-2026-elections/) |
DSCC 2022 Pennsylvania Direct Spending | $12.5 million [[^]](https://www.opensecrets.org/political-parties/DSCC/2022/expenditures-details?name=democratic-senatorial-campaign-cmte&recip=Democratic+Party+of+Pennsylvania) |

**The Democratic Senatorial Campaign Committee (DSCC) has initiated $8.5 million in 2026 ad reservations**

The Democratic Senatorial Campaign Committee (DSCC) has initiated **$8.5** million in 2026 ad reservations. For the current 2026 Senate cycle, the DSCC has made initial ad reservations totaling approximately **$8.5** million for key races in Maine and North Carolina. This includes an estimated **$3.5** million for advertising in Maine [[^]](https://bdn-data.s3.amazonaws.com/uploads/2026/03/maine_senate_ad_reservations_bdn_v3.html) and approximately **$5.0** million in ad reservations for North Carolina [[^]](https://uspollingdata.com/news/money-in-2026-elections/). Additionally, the DSCC has reported about **$0.8** million in direct spending for preliminary operations and polling specifically in North Carolina for this timeframe [[^]](https://uspollingdata.com/news/money-in-2026-elections/).

Current DSCC investments lag behind 2022's successful campaigns. In comparison to the 2022 cycle, current DSCC investment levels show notable differences. By June 30, 2022, the DSCC's direct expenditures for the successful Pennsylvania Senate race amounted to approximately **$12.5** million [[^]](https://www.opensecrets.org/political-parties/DSCC/2022/expenditures-details?name=democratic-senatorial-campaign-cmte&recip=Democratic+Party+of+Pennsylvania). At the same point in 2022, Democrats broadly, including the DSCC, had collectively reserved **$33** million in fall advertising for key Senate contests, a figure that significantly exceeds the DSCC's currently reported reservations for Maine and North Carolina in the 2026 cycle [[^]](https://digital-release.thehill.com/homenews/campaign/3471395-democrats-reserve-33-million-in-fall-advertising-in-fight-for-senate/).

## How Do Senators Cassidy and Cornyn Fare in Recent Primary Polls?

Senator Bill Cassidy (LA) Primary Lead | 3 points (March 1-4, 2026 JMC Analytics poll) [[^]](https://decisiondeskhq.substack.com/p/polls-cassidy-letlow-fleming-trump-louisiana-senate) |
Senator John Cornyn (TX) Primary Lead | 5 points (February 17-26, 2026 UT Tyler/Dallas Morning News poll) [[^]](https://www.realclearpolitics.com/epolls/2026/senate/tx/2026_texas_senate_republican_primary_paxton_vs_cornyn-8734.html) |
Vulnerability Threshold | Below 15-point margin [[^]](https://decisiondeskhq.substack.com/p/polls-cassidy-letlow-fleming-trump-louisiana-senate) |

**Senator Bill Cassidy faces potential vulnerability based on recent Louisiana primary polling**

Senator Bill Cassidy faces potential vulnerability based on recent Louisiana primary polling. Senator Bill Cassidy of Louisiana, who is up for a Republican primary on May 16, 2026 [[^]](http://www.ballotpedia.org/United_States_Senate_election_in_Louisiana,_2026_(May_16_Republican_primary)), does not have public polling data available from the final week immediately preceding this election. The most recent survey for his primary contest was a JMC Analytics poll conducted from March 1-4, 2026. This poll indicated Cassidy receiving **30%** of the vote, with his primary opponent, U.S. Representative Julia Letlow, at **27%** [[^]](https://decisiondeskhq.substack.com/p/polls-cassidy-letlow-fleming-trump-louisiana-senate). This results in a 3-point polling margin for Cassidy, which is below the 15-point threshold considered indicative of significant base erosion and general election vulnerability [[^]](https://decisiondeskhq.substack.com/p/polls-cassidy-letlow-fleming-trump-louisiana-senate).

Senator John Cornyn shows narrow lead in recent Texas primary polling. For Senator John Cornyn of Texas, whose primary elections typically occur in early March, the most recent polling was conducted by UT Tyler/Dallas Morning News from February 17-26, 2026 [[^]](https://www.realclearpolitics.com/epolls/2026/senate/tx/2026_texas_senate_republican_primary_paxton_vs_cornyn-8734.html). This poll shows Senator Cornyn with **37%** support among Republican primary voters, while his primary opponent, Ken Paxton, received **32%**, resulting in a 5-point polling margin [[^]](https://www.realclearpolitics.com/epolls/2026/senate/tx/2026_texas_senate_republican_primary_paxton_vs_cornyn-8734.html). Concluding on February 26, 2026, this poll would fall within the final week preceding an early March primary election date. Cornyn's 5-point margin is also below the 15-point threshold, suggesting potential base erosion and general election vulnerability [[^]](https://www.realclearpolitics.com/epolls/2026/senate/tx/2026_texas_senate_republican_primary_paxton_vs_cornyn-8734.html).

## What Could Change the Odds

**Key takeaway.** Catalyst analysis unavailable.

## Key Dates & Catalysts

- **Expiration:** January 07, 2027
- **Closes:** December 31, 2026

## Decision-Flipping Events

- Catalyst analysis unavailable.

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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.