US midterm election betting hits $169 million, topping 2024 congressional total
Midterm election betting volume has reached $169 million across Kalshi, Polymarket, and Polymarket US, topping the entire 2024 congressional cycle, per data cited by Reuters. Kalshi's growth rate is described as breakneck. The platforms span politics, economics, and culture. Retail and institutional adoption is rising. The data was published mid-August 2026. House and Senate races are driving the surge. Volume concentration around November's elections poses liquidity risks.
The $169 million midterm tally is concentrated on a single November event, creating a liquidity cliff that market makers must price now. For Kalshi and Polymarket, the surge means larger positions but also sharper event-risk spikes as election day approaches. Institutional desks that supplied depth in 2024 may pull back if volatility regimes look binary, and retail flow alone cannot hold tight spreads through the final weeks.
The breakneck growth also invites CFTC scrutiny on whether political markets serve a hedging purpose or function as election wagering, a distinction that determines federal legality. Both platforms are expanding contract types faster than regulators can classify them, and a midterm blowup would trigger reviews across every vertical. Kalshi's $148 billion annual run rate gives it cushion; Polymarket's $20 billion valuation target does not. The platform that keeps spreads stable through November sets the template for 2028 presidential volume.