US Midterm Elections 2026: Betfair Exchange predicts Democrats will win House and Senate

September 22 - Democrats favourites to win House and Senate in US Midterm elections 2026

Exactly six weeks out from the Midterms and the Betfair Exchange is predicting big Democrat wins across the board.

According to the odds on the Exchange - the OG of prediction betting sites - The Democrats will win control of both the House of Representatives and the Senate in the US Midterms and make Donald Trump a lame duck president for his final two years in the White House.

That is the prediction being made by the Betfair Exchange US politics markets six weeks out from the crucial votes that will take place across America on 3 November.

Below we take a look at the odds for the main Midterm betting markets on the Exchange to see where punters are placing their money ahead of an election that will have huge ramifications in the US and beyond.

House of Representatives Midterms Prediction - Democrats red-hot favourites

All 435 districts in the House are up for re-election in 2026 with the Republicans currently holding a slim 218-212 majority.

But the party are hugely unpopular and the Midterms often see the incumbent party suffer losses.

Little wonder then that the Betfair Exchange predicts a Democrat majority at odds of just 1.121/8 - that is a near 90% probability.

Senate Midterms Prediction - A closer battle but Democrats still favourites

The betting is closer in the battle for the Senate.

Of 100 seats in the Senate, 33 are up for re-election in 2026, and the Democrats need a net gain of four seat to achieve a majority.

The Betfair Exchange market has the Democrats at 1.654/6 to do that, (or a 61% probability).

Will the Democrats sweep the Midterms? Betfair Exchange predicts control of both houses

With the Democrats such short odds to win the House of Representatives and favourites to win the Senate the Exchange is offering a market on a sweep of both.

Exchange customers can currently back that outcome at 1.684/6.

There is a huge range of Midterms betting markets available on the Betfair Exchange and we will be updating the odds here, as well as providing guides and tips as we count down to the elections.

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