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- Wagering on the 2026 midterm elections across prediction markets like Kalshi and Polymarket has surpassed $220 million, more than doubling the entire $92 million volume of the 2024 congressional cycle.
- According to an analysis by the Anti-Corruption Data Collective cited by Reuters, trading is highly concentrated: the top 1% of wallets account for 70% of congressional election volume on Polymarket, and the majority of action is clustered around a few marquee Senate races, raising further scrutiny from watchdog groups regarding market integrity and the financialization of democratic processes.
More than $220 million has been wagered on 2026 midterm election outcomes across Kalshi and Polymarket, according to a Reuters report citing analysis from the Anti-Corruption Data Collective.
That total is more than double the $92 million recorded during the entire 2024 congressional election cycle, underscoring how quickly U.S. election prediction markets have expanded as the midterms approach.
Trading is concentrated in a handful of races
Reuters reported that the analysis covered more than 21,000 congressional election markets this cycle, up from 463 two years ago. But activity is not spread evenly.
Trading has been concentrated in a small number of marquee contests, especially the Texas Senate race between Ken Paxton and James Talarico. Senate races in Maine, Michigan, and South Carolina have also drawn heavy betting interest.
The report said 58% of this year’s congressional betting markets focus on victory margins, while 16% involve picking winners outright, down from 71% in 2024. Even so, bets on outright winners still account for most of the trading volume.
On Polymarket’s international platform, the top 1% of wallets accounted for 70% of congressional election trading volume this cycle, according to the analysis.
Integrity concerns are following the growth
The increase in volume has also drawn criticism from some policymakers and advocacy groups, who have raised concerns about insider trading and public confidence in elections.
Michelle Kendler-Kretsch told Reuters that election prediction markets “focus a disruptive new financial technology on our democratic process.”
Kalshi and Polymarket both pointed to monitoring and enforcement measures. Reuters reported that Kalshi has suspended a handful of candidates for wagering on their own contests. The platform also bars politicians and campaign workers from betting on elections and permanently banned George Santos after he was caught betting on whether he would attend the State of the Union earlier this year.
A Polymarket spokesperson said the company uses “state-of-the-art surveillance and dedicated detection systems built for political markets” to flag unusual activity for investigators.
Kalshi, meanwhile, has said its election markets are 98% accurate one day before voting. In comments to the New York Post, spokesperson Elisabeth Diana said, “This data is bottom-up, not elites-driven,” and called prediction markets “a way to see what people are saying when there’s money on the line.”
What to watch next
The biggest near-term question is whether volume continues to cluster around a few high-profile Senate contests or broadens across the wider congressional map as Election Day gets closer.
Another point to watch is the public and political response. A Reuters/Ipsos poll published Monday found that most Americans oppose betting on elections through prediction markets, adding another layer of scrutiny as Kalshi and Polymarket handle record midterm action.
Source: As reported by nypost.com.
