Midterm Polymarket Odds: Democrats 91.5% House, 64% Senate

Polymarket traders give Democrats a 91.5% chance of winning the House and a 64.5% chance of taking the Senate in the 2026 midterms on November 3, as of Tuesday, October 20, a gap that decides who writes crypto rules next year. The midterm Polymarket odds treat the House as close to settled. The Senate is where the money is still moving. The same split shows up in a third contract. Polymarket’s balance-of-power market prices a Democratic sweep of both chambers at 62.5% and a Democratic House with a Republican Senate at 27.5%. A Republican sweep sits at 8.5%.