Prediction Markets Face Scrutiny Over Election Integrity and Accuracy

Prediction platforms Kalshi and Polymarket are facing intense scrutiny over their impact on election integrity as they aggressively expand during the U.S. midterm elections. The platforms have launched high-profile marketing campaigns, including TV spots and a Times Square billboard, to position their odds as superior to traditional polling. More than $221 million has flowed into midterm-related markets, a significant increase from the $92 million recorded during the 2024 presidential race.

However, the Anti-Corruption Data Collective found that unusual price spikes in election contracts can distort public perception of candidate support. This was evident in the 2026 Los Angeles mayoral race, where markets heavily favored Spencer Pratt, who ultimately finished third. A Brennan Center for Justice study further indicated that voters are 10% to 20% more likely to believe a candidate will win if prediction markets favor them, regardless of actual polling data.

In response, platforms have introduced surveillance systems and transparency features to combat manipulation. Despite these efforts, officials such as Maryland State Board of Elections administrator Jared DeMarinis have called for an outright ban on election wagering to protect the legitimacy of the electoral process. Legal challenges are also mounting, with New Jersey and other states asking the Supreme Court to determine if Commodity Futures Trading Commission rules sufficiently address these concerns.