Polymarket
Republican Senate Control
58% YES
GOP favoured to keep Senate majority
Political Prediction Markets
The 2026 midterms are 5 months away. Republicans are 58% to hold the Senate and Democrats are 81% to take back the House — but Polymarket, Kalshi, and PredictIt don't always agree. Mantis shows every venue's line at once.
Click any market to see the full cross-venue comparison across Polymarket, Kalshi, and PredictIt.
Polymarket
58% YES
GOP favoured to keep Senate majority
Polymarket
81% YES
Democrats strong favourite in House
Polymarket
19% YES
Long shot for GOP to hold House
Polymarket
42% YES
Uphill for Dems to flip Senate
The same Senate control outcome can be 2–5 points apart across venues. PredictIt often diverges from Polymarket on close races. Mantis shows all three lines at once.
Prediction market odds update instantly as news breaks — polls, endorsements, candidate events. These pages revalidate every 15 minutes from live data.
Beyond the overall control markets, individual Senate races (Georgia, Nevada, Pennsylvania) have active markets. Search any race at mantiss.store.
As of June 2026, Polymarket prices Republicans at 58% to control the Senate and Democrats at 81% to control the House after the midterms. These are the most liquid US political prediction markets right now, trading hundreds of thousands of dollars daily. Kalshi and PredictIt often show slightly different probabilities on the same outcome.
Polymarket and Kalshi often price the same Senate or House control outcome 2–5 percentage points apart. This reflects different user bases and market-maker models. Mantis queries both simultaneously so you always see the cross-venue picture before deciding where to trade.
The 2026 US midterm elections are scheduled for November 3, 2026. All 435 House seats and 34 Senate seats are up for election. Prediction markets for these outcomes currently resolve in January 2027 once the new Congress is seated.
Prediction markets aggregate real-money bets from thousands of participants who have skin in the game. Research suggests they are often more accurate than polling averages because they incorporate all publicly available information and update in real time. Mantis makes it easy to compare the cross-venue consensus rather than relying on a single platform.