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. If no party wins a majority of voting seats, the chamber will be deemed controlled by the party with which the first elected Speaker of the House of the Congress that convenes after the 2026 midterm election is affiliated. The following rules govern the counting of seats for determining which party wins control of the chamber. All House elections in the 2026 United States midterm election that elect voting members and determine representation in the upcoming 120th Congress are included. Where a seat is decided by a runoff, the runoff result will determine attribution of that seat. Seats are attributed to the party under which the member was elected. If a member-elect changes party affiliation, or vacates their seat, between election day and the formal organization of Congress, the seat is attributed to the party under which the member was elected. House members elected as independents who formally caucus with, or, for newly elected members, who announce their intent to caucus with, a party are included in that party’s count. If the caucus decisions of members of the House elected as independents cannot be determined on the date of the election, this market may remain open until the earlier of (i) an announcement from the relevant members of their intents to caucus, or (ii) January 4th, 11:59 PM ET of the following calendar year. If no such announcement is made by January 4th, 11:59 PM ET of the following calendar year, the member will not count towards the seat count of any party. The resolution sources for this market will be official information from relevant state electoral authorities, the United States Congress, and a consensus of credible reporting.
Democrats hold an 88.5% implied probability of winning House control in the November 2026 midterms, while Republicans sit at 12.5%, reflecting trader consensus on a national environment favoring the opposition party. With Republicans defending a narrow majority after 2024, Democratic leads in the generic congressional ballot of roughly six points have translated into favorable shifts in race ratings across dozens of Republican-held districts. The contest functions as a referendum on the second Trump administration, whose approval ratings remain below 40% amid voter concerns over affordability and economic conditions. Mid-decade redistricting provided Republicans a modest seat cushion, yet the structural midterm penalty and limited number of competitive districts have left few paths for GOP retention. Election day on November 3 remains about ten weeks away, leaving room for late developments to influence turnout and margins in battleground seats.