Congress prediction markets track the outcomes of major legislative and political events in the United States. These markets reflect the collective forecast of thousands of participants assessing the probability of specific congressional outcomes—from Senate and House control to individual votes on confirmation hearings, legislation, and impeachment proceedings. Key markets in this category include predictions on which party will control the Senate or House, whether landmark legislation will pass, outcomes of committee votes and investigations, confirmation of executive and judicial appointments, and impeachment or censure proceedings against political figures. Prices on Congress markets move based on several factors: **Political events & announcements**: Breaking news about scandals, polling shifts, party position changes, or leadership decisions directly influence market prices. **Election cycles & demographics**: Voter registration trends, redistricting, demographic shifts, and primary results reshape expectations for congressional control. **Public sentiment**: Legislative momentum, constituent pressure, and public opinion polling often correlate with market movements on bill passage or appointments. **Member voting patterns**: Markets account for the historical voting records of specific members and their likely positions on key issues. **Timing uncertainty**: Markets reflect when events are expected to occur. A vote in the current session commands a different price than one anticipated in the next Congress. Congress markets serve as a real-time barometer of political probability. Rather than relying solely on polls or pundit analysis, these markets aggregate the financial commitments of participants across complex legislative scenarios, creating transparent forecasts of what's likely to happen next in American politics.