Republicans are fighting to retake control of the U.S. Senate from the Democrats. In 2022, Republicans lost winnable Senate races in multiple swing states—with Democrats ultimately expanding their majority by one seat. This cycle, the GOP is counting on a favorable map and a strong performance by Donald Trump to retake the chamber and—potentially—assemble a comfortable majority. Our model gives Republicans a 73% chance of retaking the Senate, projecting a 52-48 majority.
The interactive above shows which parties are leading in each Senate race. As the night goes on, winners in individual states will be projected and states will be shaded dark red or dark blue. Republicans are favored to flip West Virginia, where incumbent Joe Manchin is retiring, and Montana, where Democrat Jon Tester is facing a difficult reelection. If Republicans hold all of their seats while flipping West Virginia and Montana, they take a 51-seat majority.
Both parties are also making plays for states that the model considers them underdogs in. Republicans have focused closely on Ohio, where Republican Bernie Moreno is a slight favorite to beat Democrat Sherrod Brown. Moreno, who is expected to underrun Trump, will be hoping for a strong Trump performance in Ohio to carry him over the line. The GOP has also targeted Wisconsin, Michigan, Pennsylvania, Nevada, and Arizona. Despite close presidential polling, Democrats have maintained an edge in all five of these Senate races so far. Of these races, our model gives Republicans the best chance of scoring an upset in Wisconsin.
Democrats also have a path to keeping the majority. To do it, they will first have to sweep Ohio, Wisconsin, Pennsylvania, Michigan, Nevada, and Arizona. This would not be that surprising, but the math gets harder from there. If Kamala Harris wins the White House, Democrats would only need 50 seats to keep the majority. They could do this by holding Montana or by flipping one of Texas, Nebraska, or Florida. If they were to win two or more of those seats, they would have an outright majority.
Finally, be on the look out for deltas between performances at the presidential and senate levels. The above interactive will show which Senate candidates are outrunning Kamala Harris and where. Expect Arizona, where Ruben Gallego has been polling well ahead of Kari Lake, to be blue; conversely, expect Maryland, where former Governor Larry Hogan will probably outrun Donald Trump, to be red.