Kalshi and Polymarket Combined July Trading Volume Hits $53 Billion as US Midterms Approach

Odaily reports: Prediction market platforms Kalshi and Polymarket expanded ahead of the US midterm elections in November, with combined monthly trading volume reaching $53 billion in July, more than double the $26 billion recorded in May, with trading concentrated primarily in sports.

Political trading accounted for a relatively small share, with Polymarket averaging about $2 billion per month this year and Kalshi under $300 million; as of July, trading volume around which party controls the House and Senate had exceeded $30 million.

The US Commodity Futures Trading Commission (CFTC) had previously prohibited Kalshi from listing congressional control contracts and at one point proposed classifying election contracts as gambling. The agency withdrew the relevant proposal in February and on June 10 published a structured event contract framework proposal that would not classify elections as gambling. Kalshi launched its Midterms Hub the same month, displaying traders' implied probabilities for individual districts alongside polling averages.

Chuck Todd, former NBC News political director and former host of Meet the Press, will host the NEXTPredict summit in New York on October 22–23. He said he hopes to understand the extent to which pollsters and prediction markets need and influence each other, and whether trading is used for hedging or entertainment. Research by the Anti-Corruption Data Collective found that a $3,500 bet could move 97% of midterm election-related market prices by at least 5 cents; Morgan Stanley, after studying more than 72 million Kalshi trades, found that prices closely tracked outcomes. (Decrypt)