As the midterm elections draw near, political leaders across the United States have deemed Tuesday’s vote arguably the most significant in recent memory. With the balance of power potentially shifting on Capitol Hill, prediction markets are reflecting a favorable outlook for the Democratic Party.
By 9 AM ET on Election Day, Democrats held a 75% probability of sweeping both the Senate and the House of Representatives, according to leading prediction-market platform Kalshi. In contrast, a scenario predicting a Democratic win in the House coupled with a Republican victory in the Senate had much lower odds at 20%. Notably, the contract on Kalshi has seen over $107.8 million in notional volume.
This sentiment is mirrored on other prediction market platforms. On Polymarket’s US site, traders forecast a 77% chance of a Democratic win in the Senate, while the odds appear even higher at 78% on its offshore site. Meanwhile, DraftKings Predictions reported a 76% likelihood that Democrats will secure at least 51 seats, the minimum needed for control. The odds of a Republican victory stood around 27% on DraftKings during an oversubscribed market, with leading prediction markets estimating Democrats’ chances of regaining the House at over 90%.
At recent prediction market conferences, such as Predict 2026 and NEXTPredict, the surge in trading around election contracts was a key discussion point. Chuck Todd, former moderator of Meet The Press, warned that inexperienced retail traders could face significant losses on Election Night if they fail to monitor exit polling data closely in real-time.
Another trending topic was the rise of "multi-step conditional contracts," which require a specific event or condition to be met before they can be settled. Polymarket is offering several of these contracts based on a potential Democratic sweep. One such contract allows traders to wager on a Democratic candidate winning the 2028 Presidential Election if Democrats sweep Congress, with odds currently at 73% as of Tuesday morning.
Additionally, traders on the platform are speculating on various economic and geopolitical events. They see a 35% chance of a US recession by the end of 2027, while the likelihood of a US-Iran ceasefire holding through 2027 is rated at just 3%.
Close races are anticipated in at least four Midwest states—Michigan, Ohio, Kansas, and Iowa—indicating that the resolution of Senate control contracts may not be clear by Wednesday morning.
Overall, trading volume across US prediction markets has surged dramatically compared to the midterms held two years prior. As of Tuesday morning, the midterm election contracts across all platforms have surpassed $1.48 billion in notional volume.
