Which party will win the Senate in 2026? — odds by venue

As of Oct 20, 2026, 09:42 UTC, Democratic Party trades at 65% on Polymarket and 67% on Opinion. Combined volume: $88.6K.

Venues

• Polymarket: Volume $88.4K · Liquidity $6.4M · Price time —
• Opinion: Volume $179 · Liquidity $5.4M · Price time —

Resolution rules

Polymarket

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. If no party wins a majority of voting seats, the party that wins control of the chamber is the party that wins half of the voting seats and holds the Vice Presidency. If the outcome remains ambiguous after applying the above criteria, the chamber will be deemed controlled by the party with which the first selected President Pro Tempore of the Congress that…

Opinion

This market will resolve according to the party that controls the Senate following the 2026 U.S. Senate elections scheduled for November 3, 2026. Senate control is defined as having more than half of the voting Senate members, or half of the voting Senate members and the Vice Presidency. If the outcome of this election is ambiguous given the above rules, this market will remain open until the Majority Leader of the US Senate is selected following the 2026 US general election, at which point it will resolve to the party the majority leader is affiliated with at the time of their election to…