Polymarket: Democrats Now 51% Favorites to Sweep Midterms

Democrats now have a 51% probability of winning both chambers of Congress in November, according to the crypto-based prediction market Polymarket. President Trump's approval rating is declining, and gas prices have reached a new all-time high.

These odds have shifted rapidly. A year ago, a Democratic sweep was at just 26%, and one month ago it stood at 45%.

Democrats Gain Ground as Trump’s Support Slides

Polymarket's Balance of Power market for the 2026 midterms assigns Democrats a 51% chance of a sweep. The House appears locked up, with Democrats holding 89% odds. The Senate race is tighter, with Democrats also at 51%.

Currently, Republicans control both chambers. The elections are scheduled for Nov. 3.

Trump’s Approval Rating Drops for A Number of Reasons

The shift in odds follows Trump's falling approval ratings. Some surveys place his support between 32% and 34%.

A poll by the Financial Times and FocalData found that most Americans say their finances have deteriorated under Trump. A majority of independents agreed.

Another survey by Reuters and Ipsos shows Democrats now slightly edge out Republicans on the economy. The margin is 37% to 36% in favor of Democrats, ending nearly a decade of Republican advantage on that issue.

Rising gas prices are adding to the pressure. The national average hit a record $4.056 per gallon in August.

That tops the previous high of $3.940 from 2022. The ongoing conflict with Iran keeps energy markets unsettled.

Trump has defended the price spikes as a necessary cost of pushing Iran toward denuclearization. He said he would not apologize because he believes he did the right thing.

Trump has also sought to secure Venezuelan oil supplies. He met with industry executives this week in an effort to cool prices.

Election Day is two months away. The key question is whether Republicans can reverse the slide or if Polymarket's probabilities will continue drifting toward a Democratic sweep.