Overview
- Prediction markets priced a Democratic 'blue wave' well before voting, with major platforms putting high odds on House and Senate control in the closing weeks of the campaign.
- On Election Day those markets updated in real time and signaled Democratic control before official counts, and Kalshi reported favorites winning roughly 479 of 487 resolved contests for about a 98% hit rate.
- Kalshi said midterm trading topped roughly $2.5 billion on its platform and other outlets reported nearly $1.9 billion wagered across platforms, driven by both hobby bettors and a small number of very large wagers.
- The markets’ performance has prompted stepped-up oversight: senators sent pre‑election letters, several states have pursued gambling-law cases, and the Commodity Futures Trading Commission says it is monitoring contracts for manipulation.
- Coverage and research praise improved calibration but also flag integrity risks such as concentrated liquidity, thin markets in some races, large single bets, and potential insider trading that could prompt new laws or enforcement actions.