Prediction Markets Signal Likely Democratic Sweep as Midterm Election Day Begins
Prediction markets like Kalshi and Polymarket show high odds for a Democratic takeover of the House and Senate as voters head to the polls today.
POLICY WIRE — Washington, D.C. — As Americans head to the polls on Tuesday, prediction markets are signaling a significant shift, forecasting a potential Democratic victory across both chambers of Congress.
Data from the forecasting platform Kalshi currently indicates a 76 percent probability that Democrats will seize control of both the U.S. House and the Senate. This represents a sharp increase compared to January, when the odds of a Democratic double-sweep were valued at just 28 percent.
Bettors on Kalshi also factored in a 20 percent chance of Democrats winning the House while the Republicans maintain their hold on the Senate. Meanwhile, the likelihood of a total Republican sweep currently sits at a low 6.5 percent.
Similar trends are appearing on Polymarket, another major online platform for forecasting. As of Tuesday, users of the site placed a 77 percent chance on Democrats taking over the Senate, leaving Republicans with a 23 percent probability of retaining their current status.
The influence of these platforms has drawn attention via Donald Trump Jr. The president’s son became an adviser for Kalshi last year, receiving shares valued at approximately $300,000. He also joined the advisory board of Polymarket in August 2025, with a press release noting an undisclosed investment made through his venture capital fund, 1789 Capital.
While President Trump does not appear on the ballot today, he has urged his base to vote as if he were campaigning. These market movements come despite various polls suggesting a difficult path for GOP candidates, driven by public dissatisfaction regarding rising living costs and foreign policy issues in Iran.
In the Texas Senate race, Democratic James Talarico is seen as a close contender against Republican Attorney General Ken Paxton. The House of Representatives remains a primary battleground, where the GOP currently holds 219 seats to the Democrats’ 214, requiring 218 votes to secure a majority.
Reporting by Policy-Wire (PW)
