New Hampshire Senate race odds 2026: Sununu vs. Pappas
An open seat after Jeanne Shaheen chose not to run again: Democratic congressman Chris Pappas faces Republican John E. Sununu, a former senator.
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Sikt’s forecast
Sikt gives Chris Pappas a 92% chance. Latest Sikt Midterm Bench round: Nov 3, 2026.
Sikt’s read
- History favors Democrats. They have won five of the last six New Hampshire Senate races; the last Republican win was in 2010.
- The polls favor Pappas. He leads all five polling averages by 6.5 to 7.3 points. The final polls have him up 12 (UNH), 8 (AtlasIntel) and 6 (a Republican-sponsored poll), and every Republican-sponsored poll in October had him ahead by 5 to 7.
- The year helps him. The national generic ballot is about D+9, Trump is unpopular in the state, and Sununu's net favorability fell to −18 in UNH's final poll.
- What holds Sikt back: Sununu's family name, ticket-splitting and heavy Republican outside spending. Sununu would need a polling miss of 7 points or more, which is rare but has happened (Florida, 2022).
- Bottom line: Pappas is a clear favorite, a touch firmer than last round. Sikt and the market agree.
How much will they win by?
Sikt’s middle estimate: Pappas by 8.5 points. Its 80% range runs from Pappas by 3.0 to Pappas by 14.2, so the result should land inside it 8 times in 10. Kalshi has no margin market for this race.
Margin is the winner’s lead in share of the vote, in percentage points. Round 13, Nov 3, 2026. Scored against the certified result. Every race: 2026 Senate race margins.
Every round
Chance Chris Pappas wins. Market prices are from the same day; the gap is Sikt minus the average of the two markets, in points. Version is the release of Sikt that made the forecast.
| Round | Date | Sikt | Kalshi | Polymarket | Gap | Version |
|---|---|---|---|---|---|---|
| R13 | Nov 3 | 92% | – | – | – | 1.12 |
| R12 | Nov 2 | 91% | – | – | – | 1.12 |
| R11 | Oct 31 | 90% | – | – | – | 1.12 |
| R10 | Oct 29 | 89% | – | – | – | 1.12 |
| R9 | Oct 27 | 89% | – | – | – | 1.12 |
| R8 | Oct 24 | 89% | – | – | – | 1.12 |
| R7 | Oct 21 | 87% | – | – | – | 1.12 |
| R6 | Oct 18 | 90% | – | – | – | 1.6 |
| R5 | Oct 15 | 88% | – | – | – | 1.6 |
| R4 | Oct 12 | 87% | – | – | – | 1.6 |
| R3 | Oct 9 | 88% | – | – | – | 1.6 |
| R2 | Oct 3 | 86% | – | – | – | 1.2 |
| R1 | Sep 30 | 85% | – | – | – | 1.0 |
Every forecast will be graded against the result. More on the Sikt Midterm Bench. Not financial advice.
The markets
Who will win the New Hampshire Senate race?
| Outcome | Kalshi | Polymarket | Average |
|---|
What to know
- Open seat: no incumbency advantage for either side.
- Lean: New Hampshire has elected Democrats to the Senate in recent cycles.
- Election day is Tuesday, November 3, 2026. Odds usually move most in the final weeks, on polls, early-vote data and news. See all races on the 2026 midterms page.
How these markets resolve
- Kalshi, “New Hampshire Senate winner?”: If a representative of the Republican party is sworn in as a Senator of New Hampshire for the term beginning in 2027, then the market resolves to Yes. Full rules
- Polymarket, “New Hampshire Senate Election Winner”: This market will resolve according to the winner of the 2026 midterm New Hampshire U.S. Senate election, inclusive of any run-offs. A candidate shall be considered to represent a party in the event that he or she is the nominee of the party in question. Full rules
How to read these odds
A price of 30¢ on a contract that pays $1 means the market puts the event at roughly 30%. Prices move with supply and demand, include fees and spreads, and can lean on long shots. When the two markets disagree by more than a few points, check whether their rules or deadlines differ. More in how prediction markets work and the favorite-longshot bias.
FAQ
Who is favored in the New Hampshire Senate race?
These are market prices, roughly the probability traders are willing to bet on, not a guarantee.
Why do Kalshi and Polymarket show different odds?
They are separate markets with different traders, fees and sometimes different rules or deadlines. A gap of a few points is normal; a large gap is worth checking against each market's rules.
How often are these odds updated?
Sikt refreshes this page from Kalshi's and Polymarket's public data several times a day. The time of the last update is shown at the top.
Are prediction market odds accurate?
Often, but not uniformly. Research on Kalshi finds prices are informative and improve as a market nears its close, but long shots tend to be overpriced (the favorite-longshot bias).
Market data from the public Kalshi and Polymarket APIs, shown for information only. Prices are midpoints or last trades and can be several hours old. Sikt Intelligence is not affiliated with Kalshi or Polymarket. Not financial or investment advice.