U.S. Midterm Election Bets Near $1.5 Billion as Prediction Markets Face Accuracy Test

Bets on the U.S. midterm elections have climbed to nearly $1.5 billion, putting prediction markets that correctly called the last presidential election to a fresh test.

Reuters reported on November 3 that more than $1.48 billion had flowed into prediction markets ahead of the U.S. midterms. Kalshi drew $1.33 billion, while Polymarket attracted $145 million.

Data from prediction-market analytics firm BetInt showed that, as of November 2, Democrats had a 95% chance of retaking the House and a 76% chance of controlling the Senate.

The midterms are emerging as a test of the credibility of prediction markets. In the 2024 presidential election, Polymarket and Kalshi drew attention for predicting Donald Trump's victory even as opinion polls pointed elsewhere.

“The midterms will be a real test for these new prediction markets,” Yesha Yadav, associate dean at Vanderbilt Law School, said. With many closely contested races, the election offers a chance to assess how well the markets perform, Yadav added.