How will the U.S. Senate map look for 2024? 

By Colby Etherton

With a presidential election on the horizon next year, it can be easy to forget that the Senate, House of Representatives, and local races are just as integral in shaping policy. After the unexpected over-performance of Democrats in the 2022 midterms when Democrats gained a seat in the Senate, a mythos that elections are becoming more of a mystery, as voters increasingly separate feelings on a sitting president from candidates running in their states, is beginning to form. Approximately 33 seats are up for election in 2024’s elections, with the map on the surface seeming to favor Republicans. 

Most states that are considered toss-ups happen to have seats that Democrats will be defending — a position that a party typically wants to avoid. States that Democrats are defending include Montana, Ohio, West Virginia, and Nevada. Notably, the first three are states that former president Donald Trump won in both 2016 and 2020. Democratic Senators in Republican states (Jon Tester in Montana, Sherrod Brown in Ohio, and Joe Manchin in West Virginia) will all face tough reelection races that threaten to flip the Senate chamber to Republican control. Currently, Democrats have a 51 to 49 majority, taking into account that three independent senators (Angus King of Maine, Bernie Sanders of Vermont, and Kyrsten Sinema of Arizona) caucus with Democrats. Republicans winning the White House in 2024 means they’d only need a net gain of one seat, as Vice Presidents break ties in a 50-50 Senate. 

In the case of Nevada, a state that perpetually has razor-thin election margins between Democrats and Republicans, Democratic Senator Jackie Rosen will be defending her seat. Notably, Catherine Cortez-Masto narrowly won reelection in Nevada by less than a point in 2022 — underscoring the inevitably tight race that Rosen will face. 

Arizona will be one of the more interesting states in next year’s elections, as Independent Sen. Kyrsten Sinema is being challenged from the left by Democratic Rep. Ruben Gallego and will face a challenger from a Republican candidate, as well. In what will inevitably be a three-person race, it’s unclear if Democrats will turn out for her or Gallego, and both have the potential to split votes and hand the seat over to Republicans. 

Republican Senators tend to defend seats in states that are strongholds for their party, but a window of opportunity may present itself in Texas against Sen. Ted Cruz, who is perpetually unpopular and tends to be embroiled in some form of controversy. While Texas has long been considered a ruby-red conservative bastion, Cruz won reelection in 2018 by less than three points against challenger Beto O’Rourke. 

Most states won’t have competitive Senate races going into 2024, but the handful that are will be integral to shaping policy over the next several years. The good news for Democrats is that Biden’s relative unpopularity in 2022 didn’t help facilitate a red wave, meaning that no matter what happens on the presidential level, they just may squeak out another upset in the Senate.