US midterm predictions: Democrats tipped to sweep Congress as market odds climb
Markets favor a Democratic sweep
Kalshi’s Tuesday afternoon estimates gave Democrats an 80 percent chance of taking the Senate and a 95 percent chance of winning the House. In January, the platform had put the odds of Democrats winning both chambers at 28 percent.
Kalshi gave Democrats an 18 percent chance of taking the House while Republicans kept the Senate. The odds of a Republican sweep were 3.9 percent, according to bettors on the platform.
Polymarket gives similar outlook
Polymarket bettors put Democrats’ chances of winning the Senate at 75 percent, while giving Republicans a 26 percent chance of retaining it. In a separate House market, the platform showed a 95 percent chance for Democrats and a 6 percent chance for Republicans to hold the chamber.
The House figures marked the highest market estimate for Democrats and the lowest for Republicans since July 2025. The platforms’ numbers are predictions, not election results.
Election stakes and party balance
Millions of Americans were voting Tuesday, with the first results expected within hours. Trump was not on the ballot, but had urged supporters to act as if he were.
Republicans held a 53-to-47 Senate majority, with two independents who usually vote with Democrats. Thirty-five Senate seats were up for election. In the House, Republicans held 219 seats to Democrats’ 214, and 218 seats were needed for a majority.
Campaign pressures and connections
The article cited public anger over rising living costs and Trump’s unpopular war in Iran as factors behind grim polling for Republican candidates. A POLITICO poll conducted by PF Global found that about 9 percent of Trump’s 2024 voters planned to vote for a Democrat in the midterms.
Democratic candidates had gained ground even in states described as deeply Republican. In Texas, Democrat James Talarico was neck and neck with Republican Attorney General Ken Paxton in the Senate race.
Key points
- Kalshi put Democrats’ chances at 80 percent for the Senate and 95 percent for the House.
- Polymarket also showed strong odds for Democrats in both chambers.
- Republicans held narrow majorities in the Senate and House before the election.
- Trump was not on the ballot, but urged supporters to treat the election as if he were.