2026 midterm election odds: House and Senate
Americans vote on November 3, 2026 for all 435 House seats and about a third of the Senate. These are the prediction market odds for which party controls each chamber, side by side from Kalshi and Polymarket with 90 days of history, next to Sikt's own AI forecast for the House, the Senate, the seat counts and every key Senate race.
Democrats win the House
Polymarket
94%
At Sikt’s forecast, Nov 3 · now >99%
Democrats win the Senate
Polymarket
76%
At Sikt’s forecast, Nov 3 · now >99%
The Senate races that decide control
Closest races first, by the average of Kalshi and Polymarket. Sikt’s latest forecast is shown first, and in green on each chart. Each card links to live odds, Sikt’s read, history and the market rules.
How much will each race be won by?
Sikt’s middle estimate of the winner’s lead, in points, its 80% range (the result should land inside it 8 times in 10) and Kalshi’s margin markets at the start of round 13, Nov 3, 2026. Closest races first. In the chart, Democrats (and in Nebraska, the independent Osborn) are to the right of the middle line. How to read the margins →
| Race | Sikt | Sikt’s 80% range | Market | R ← → D |
|---|---|---|---|---|
| Alaska | Peltola +1.0 | Sullivan +5.4 to Peltola +7.0 | Peltola +2.6 | |
| Iowa | Hinson +1.2 | Hinson +7.2 to Turek +4.6 | Turek +0.3 | |
| Kansas | Hamilton +2.0 | Marshall +5.2 to Hamilton +8.2 | Hamilton +1.4 | |
| Ohio | Brown +2.1 | Husted +3.4 to Brown +7.3 | Brown +3.4 | |
| Texas | Talarico +2.4 | Paxton +3.4 to Talarico +8.0 | Talarico +3.0 | |
| South Carolina | Graham +2.8 | Graham +9.2 to Andrews +3.5 | Graham +1.2 | |
| Nebraska | Ricketts +3.1 | Ricketts +9.5 to Osborn +3.1 | Ricketts +3.0 | |
| Maine | Jackson +3.2 | Collins +4.0 to Jackson +10.1 | Jackson +2.4 | |
| Michigan | El-Sayed +5.0 | Rogers +0.6 to El-Sayed +10.6 | El-Sayed +3.6 | |
| Minnesota | Flanagan +7.6 | Flanagan +1.7 to Flanagan +13.4 | Flanagan +7.4 | |
| Georgia | Ossoff +8.3 | Ossoff +2.8 to Ossoff +13.9 | Ossoff +11.4 | |
| New Hampshire | Pappas +8.5 | Pappas +3.0 to Pappas +14.2 | – | |
| North Carolina | Cooper +9.7 | Cooper +4.1 to Cooper +14.9 | Cooper +13.2 |
Seats, Sikt’s middle estimate and 80% range: Senate: Democrats win 52 seats (48 to 55), market 52 or fewer; House: Democrats win 230 seats (219 to 243), market 241; House popular vote D +8.2, market D +9.8.
Sikt’s forecast
Sikt gives Democrats a 91% chance of winning the House and a 75% chance of winning the Senate, against 94% and 76% on the markets at the time. Latest Sikt Midterm Bench round R13: Nov 3, 2026.
Sikt is an AI superforecaster: it reads the news and data that exist on the day, and puts its own probability on each outcome. Its forecast is the green line in the charts above.
Every round
Chance Democrats win control. Market is the average of Kalshi and Polymarket on the same day.
| Round | Date | House: Sikt | Market | Senate: Sikt | Market |
|---|---|---|---|---|---|
| R13 | Nov 3 | 91% | 94% | 75% | 76% |
| R12 | Nov 2 | 90% | 94% | 71% | 72% |
| R11 | Oct 31 | 92% | 94% | 66% | 70% |
| R10 | Oct 29 | 88% | 92% | 64% | 68% |
| R9 | Oct 27 | 90% | 92% | 60% | 66% |
| R8 | Oct 24 | 90% | 92% | 64% | 68% |
| R7 | Oct 21 | 90% | 92% | 65% | 64% |
| R6 | Oct 18 | 91% | 90% | 66% | 64% |
| R5 | Oct 15 | 89% | 90% | 59% | 64% |
| R4 | Oct 12 | 89% | 90% | 63% | 64% |
| R3 | Oct 9 | 89% | 90% | 55% | 62% |
| R2 | Oct 3 | 88% | 92% | 56% | 64% |
| R1 | Sep 30 | 87% | 92% | 53% | 62% |
Every forecast will be graded against the result. Each chamber in full: House forecast · Senate forecast. Not financial advice.
How many seats?
Not only who wins, but by how much. Sikt’s middle estimate and 80% range (the result should land inside it 8 times in 10), next to Kalshi’s seat and vote-margin markets at the start of round 13, Nov 3, 2026. Scored after the election. More in how many seats will Democrats win?
Democratic Senate seats
Sikt 52 (80% range 48 to 55) · Kalshi 52 or fewer (48 to 53+)
Seats Democrats hold on February 1, 2027, counting independents who caucus with them. Democrats hold 47 now and need 51 for control, because the vice president breaks ties for Republicans.
Democratic House seats
Sikt 230 (80% range 219 to 243) · Kalshi 241 (217 to 243+)
Seats Democrats hold on February 1, 2027, out of 435; 218 is a majority. Shown as 435 minus the forecast for Republican seats.
House popular vote
Sikt D +8.2 (80% range D +4.7 to D +11.7) · Kalshi D +9.8 (D +4.9 to D +14.1)
Democrats’ lead in the national vote for the House, in points.
The markets
Which party will win the House?
Kalshi · 207.3M contracts traded · Polymarket · $61.9M traded
| Outcome | Kalshi | Polymarket | Average |
|---|---|---|---|
| Democrats | – | >99% | |
| Republicans | – | <1% |
Which party will win the Senate?
Kalshi · 115.4M contracts traded · Polymarket · $31.0M traded
| Outcome | Kalshi | Polymarket | Average |
|---|---|---|---|
| Democrats | – | >99% | |
| Republicans | – | <1% |
What to know
- Results: polls close on the evening of November 3, local time, and close races can take days to call. State by state: when will we know the midterm results?
- Base rate: the president's party has lost House seats in every midterm since World War II except two, 1998 and 2002. That history is a strong headwind for the party in the White House.
- The House is decided by all 435 seats; a majority is 218.
- The Senate depends heavily on which seats happen to be up this cycle, so national mood matters less than the map.
- Odds move on polls, special elections, retirements and campaign finance reports, and usually most sharply in the final weeks.
How these markets resolve
- Kalshi, “Who will control the House?”: If the Democratic Party has won control of the House in 2026, then the market resolves to Yes. Full rules
- Polymarket, “Which party will win the House in 2026?”: This market will resolve according to the party that wins control of the United States House of Representatives in the 2026 United States midterm election. A party wins control of the United States House of Representatives if it wins a majority of the chamber’s voting seats. Full rules
- Kalshi, “Who will control the Senate?”: If the Democratic Party has won control of the U.S. Senate in 2026, then the market resolves to Yes. Full rules
- Polymarket, “Which party will win the Senate in 2026?”: This market will resolve according to the party that wins control of the United States Senate in the 2026 United States midterm election. A party wins control of the United States Senate if it wins a majority of the chamber’s voting seats. 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 to win the House in the 2026 midterms?
As of Nov 4, 2026, Polymarket prices it at >99%. These are market prices, roughly the probability traders are willing to bet on, not a guarantee.
What does Sikt's AI forecast say about the 2026 midterms?
In its latest Midterm Bench round, Sikt Intelligence's AI forecast gives Democrats a 91% chance of winning the House and a 75% chance of winning the Senate. Every forecast will be graded against the results.
How many seats will Democrats win in 2026?
Sikt's middle estimate in round 13: Democrats win 230 House seats (80% range 219 to 243; 218 is control) and 52 Senate seats (80% range 48 to 55; 51 is control). The result should land inside each range 8 times in 10.
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.