Pre-election betting markets pointed toward a Democratic victory in the 2026 U.S. midterms, and their broad direction matched the result, according to an analysis by Jeremy Horpedahl published Wednesday.
In a Nov. 4 post for Economist Writing Every Day, Horpedahl reviewed a Senate map from ElectionBettingOdds.com based on the night before voting. He said the markets favored Democrats overall, but did not clearly indicate the scale of the party’s victory.
The map showed Iowa as a toss-up. An average across three betting markets gave Mississippi’s Democratic candidate a one-in-seven chance; Horpedahl described the outcome there as a major surprise. He also noted that every state marked above 90% odds for one party was won by that party.
Horpedahl cited a recent paper in the Proceedings of the National Academy of Sciences as broader evidence about prediction markets. He said the paper found that market probabilities generally corresponded with how often events occurred across a range of outcomes.
