US House Odds Favour Democrats at 91%

Traders now put the chance of Democrats winning the US House at about 91%, according to the two biggest prediction markets, with 10 days to the 2026 US midterm elections on Tuesday, 3 November. The Senate is far closer, at about 67%.
Key Facts
- Prediction markets, House: Democrats 91.5% on Polymarket and 91% on Kalshi, as of 11:50 p.m. ET, 23 October.
- Prediction markets, Senate: Democrats 67.5% on Polymarket and 67% on Kalshi, same time.
- Latest poll: New York Times/Siena, 21 October: Democrats lead the House ballot 52% to 41% among likely voters.
- Senate math: Republicans hold 53 of 100 seats, so Democrats need a net gain of four.
- Election Day: Tuesday, 3 November 2026; each state sets its own polling hours.
This story is part of our coverage of the 2026 US midterm elections. Dates, times and how to follow it are in our guide.
What Prediction Markets Say
At 11:50 p.m. ET on 23 October, Polymarket priced a Democratic House at 91.5% (about US$21.1 million traded) and Kalshi at 91%. For the Senate, Polymarket showed Democrats at 67.5% (about US$8.8 million traded) and Kalshi at 67%.
Polymarket’s “Democrats Sweep” contract, which pays if Democrats win both chambers, stood at 66.5%, down 2 points in 24 hours. Republicans keeping the Senate while losing the House stood at 24.5%.
These prices are real-money bets, not polls, and they can move within minutes. Kalshi is regulated in the US by the CFTC, the federal derivatives regulator.
Why we show this: prediction markets turn real-money bets into a live probability that moves within minutes of the news, which is why investors, campaigns and newsrooms in the United States now follow them closely. We show them next to polls and official results, never instead of them.
Why the Senate Is Harder
Republicans hold 53 of the 100 Senate seats, while Democrats and two independents who vote with them hold 47. A 50-50 split would be broken by the Republican vice president in the Republicans’ favour.
Democrats therefore need a net gain of four seats for a majority. The Cook Political Report, a nonpartisan forecaster, projects a Democratic gain of two to six Senate seats, a range that leaves control open.

Polls and Close Races
The New York Times/Siena College poll, released on 21 October, found Democratic House candidates ahead 52% to 41% among likely voters. It also put President Donald Trump’s approval at 36%, with 59% disapproving, the lowest in any Times/Siena poll.
In the same poll, 69% disapproved of Trump’s handling of the cost of living and 65% of the Iran war. Harvard’s Institute of Politics, in a survey released on 22 October, found Democrats ahead 63% to 26% among 18-to-29-year-olds who say they will definitely vote.
In Colorado’s 3rd District, a Democratic Congressional Campaign Committee poll of 402 likely voters on 20-21 October had Democrat Dwayne Romero at 47% and Republican Jeff Hurd at 46%, within its 4.9-point margin of error. In South Carolina’s 1st District, a poll sponsored by the Democratic group House Majority PAC on 21-22 October had Democrat Nancy Lacore at 47% and Republican Jenny Costa Honeycutt at 45%, while Polymarket priced Honeycutt at about 60%.
What to Watch
About 23 million ballots had been cast by 23 October, according to the TPS Elections early-vote tracker. That total does not show who is winning, because the party split of early voters is not a result.
The Federal Reserve’s next rate decision is due on Wednesday, 28 October, at 2:00 p.m. ET (18:00 UTC), six days before Election Day. Our guides explain when polls close and how the midterm odds work.
What It Means for US Readers
The markets treat the House as close to settled, while control of the Senate is still open. That gap matters for anyone following judicial confirmations, the federal budget or trade policy, because the Senate handles all three.
Prices are a snapshot and can shift with each new poll or early-vote report. A reader who wants the wider picture can start with our explainer on the 2026 midterms.
What Is Not Known
Whether the Democratic lead will turn into the seats needed for Senate control is not known. Late-deciding voters, turnout and remaining early voting could narrow or widen it.
Sponsor-funded district polls may not reflect the final electorate, and market prices may change before 3 November. Ballot totals and race results stay unknown until votes are counted and certified.
Sources
Polymarket (House, Senate) and Kalshi, read at 11:50 p.m. ET on 23 October 2026; New York Times/Siena College poll, 21 October; Harvard Kennedy School Institute of Politics; Colorado Public Radio; Cook Political Report; TPS Elections.
This article was produced by The Rio Times’ automated newsroom system. How we use AI · Report an error · Editorial responsibility: Matthias Camenzind, Editor-in-Chief
Frequently Asked Questions
What are the odds Democrats win the House and Senate?
As of 11:50 p.m. ET on 23 October 2026, Polymarket priced a Democratic House at 91.5% and Kalshi at 91%. For the Senate, Polymarket showed 67.5% and Kalshi 67%.
How many Senate seats do Democrats need?
Democrats need a net gain of four seats for a majority. Republicans hold 53 of 100 seats, and a 50-50 split would be broken by the Republican vice president.
Are prediction markets the same as polls?
No. Prediction markets show real-money bets, which turn into a live probability, while polls survey a sample of voters. We show them next to polls and official results, never instead of them.
When is Election Day for the 2026 midterms?
Election Day is Tuesday, 3 November 2026. Each state sets its own polling hours, so results begin to appear as local polls close.