Prediction market trading on the 2026 US midterms has exceeded $750 million, nearly eight times the volume on congressional and state races in 2024. The growth is drawing attention to the platforms’ expanding political markets as regulators and sports leagues debate how event contracts should be overseen.
Midterm contracts surge
Polymarket CEO Shayne Coplan has described the 2024 presidential election as a turning point for prediction markets. After a landmark court victory opened a legal route for Americans to trade political contracts, Polymarket showed Donald Trump at about 58% as polls closed, while NBC News and other networks had reported a close race against Kamala Harris. A Fox Business commentator said, “Polymarket was spot on the entire time.”
Coplan called the moment “one of the most gratifying” on the Netflix program Instadoc: The Prediction Games, saying it changed the industry’s credibility. The 2026 midterms are now generating more than 21,000 markets on Kalshi and Polymarket. The Anti-Corruption Data Collective estimates volume could reach $1.6 billion once the elections are over. In 2024, trading on races other than the presidential contest totalled $92.4 million.
Author James Surowiecki said the midterms would be “one of the biggest tests for prediction markets” because of the stakes involved. Trading volume had passed $750 million by 15 October.
NBA restricts some props, but has no CFTC agreement
The NBA and its official sportsbook partners agreed on Friday to restrict certain player props ahead of next week’s regular-season opener. Props will not be offered on reserve players expected to play fewer than 12 minutes, and customers will no longer be able to combine multiple unders on one player’s statistics. That rules out, for example, a single-game under combination on LeBron James’ points, rebounds and assists.
Polymarket still offered a $10 three-leg combination on James’ Philadelphia 76ers debut, with a $14.19 payout. Kalshi had no NBA under-combo markets listed on Friday night. The league has held formal talks with the US Commodity Futures Trading Commission (CFTC) about an integrity framework for basketball event contracts, but has not signed a Memorandum of Understanding. NBA executive vice president Scott Kaufman-Ross said restrictions could be difficult without an agreement. The league is also facing prop-manipulation scandals, with several former players due to stand trial in the coming months.
CFTC defends proposed swap rules
On 9 October, the CFTC proposed a broader definition of financial swaps that would classify sports and political event contracts as swaps. The Commission says it has exclusive authority over derivatives; most state attorneys general disagree, leaving open the possibility of a Supreme Court fight.
Chair Michael Selig said the agency is focused on insider trading, wash trading, fraud and other manipulation. The CFTC and Justice Department have begun investigating $2.6 billion in oil trades made near the start of the US-Iran conflict. The CFTC also examined about $5 billion in Kalshi trading linked to bitcoin perpetual futures; Kalshi denied wash trading allegations.
Speaking to Fox Business on 15 October, Selig said the CFTC regulates commodity markets every day, adding: “My concern is that you can’t offer an order book in a casino, that’s not how these wagers work when they are placed with a bookie.”
