The over-performance of the Democratic Party in midterm Senate races, resulting in a net gain of one seat, represented a mild upset. If Democrats hang on to their fragile control of the chamber in 2024, it will be truly amazing.
The Senate’s six-year terms mean that senators are divided into “classes” of 33 or 34 lawmakers who face voters the same year. And that means the landscape can vary significantly from cycle to cycle regardless of what else is going on politically. Class 1 will be up for reelection next year, when the landscape will be very, very difficult for Democrats. For one thing, they are defending 23 seats while Republicans are defending 11 (including a Nebraska seat just filled by an appointment which will last only until a 2024 special election). But worse yet, some of those 23 Democratic seats are in difficult terrain, as Sabato’s Crystal Ball explains in its initial Senate forecast:
Democrats are defending all 3 seats they hold in states that Donald Trump carried for president in 2020 — Montana, Ohio, and West Virginia. Additionally, they are defending 5 more in states that President Biden carried but by margins smaller than his national edge (roughly 4.5 points). Those are Arizona, Michigan, Nevada, Pennsylvania, and Wisconsin.
It tells you everything you need to know about Republican Senate vulnerabilities in 2024 that probably the two most promising takeaways for Democrats are in Florida and Texas. The other eight states (Nebraska has two races) whose Senate seats the GOP holds are very red indeed (Indiana, Mississippi, Missouri, Nebraska, North Dakota, Tennessee, Utah, and Wyoming).
The precise peril faced by Democrats will depend on a couple of potential retirements. If Jon Tester of Montana and Joe Manchin of West Virginia run again, they will be underdogs from the get-go but have a chance. If they instead retire, their seats will very likely flip. Manchin is without question the most vulnerable Democrat in 2024 (with the possible exception of his Arizona friend Kyrsten Sinema, who actually no longer identifies as a Democrat) given his state’s heavy GOP tilt in presidential years (Donald Trump won the state by 42 points in 2016 and 39 points in 2020) and the crowd of formidable Republicans already lining up to challenge him. Manchin will be 77 years old in 2024.
The Arizona race shows that Democrats won’t have an easy path to victory even in states Joe Biden carried in 2020 and where the party did well in 2022. Early polling shows that Sinema may have simply worn out her welcome among Democrats angry at her heresies and Republicans who may appreciate her defense of the filibuster but aren’t going to back an openly bisexual pro-choice former Democrat who voted twice to impeach Trump. But any residual Democratic support Sinema and her flush campaign account can retain will hurt likely Democratic nominee Ruben Gallego — even if the GOP candidate is (as is entirely possible) failed 2022 gubernatorial candidate and MAGA ultra Kari Lake.
There are potential bright spots for Democrats, to be sure. One of the incumbents running in a red state, Ohio’s Sherrod Brown, is a strong campaigner with “populist” street cred who has bucked conservative tends in his state repeatedly in the past. And given the relatively strong performance of Democratic Senate candidates in Florida and Texas six years ago (albeit in a very good Democratic year), Republican incumbents Rick Scott and Ted Cruz are hardly home safe, and either or both of them might instead run for president.
All in all, though, Sabato’s Crystal Ball suggests that the Senate landscape for Democrats is reminiscent of the one they faced in 2014, which did not turn out well:
It isn’t necessarily a stretch to say that Democrats are defending the top 8 Senate seats likeliest to flip. This level of exposure may feel unusually significant at the start of a cycle, although Democrats were also greatly exposed heading into the 2014 Senate elections — in our first update that cycle, we suggested that at least the 7 most vulnerable seats were held by Democrats. Democrats ended up losing all 7 of those seats, plus 2 more for a total of 9 as Republicans flipped the Senate.
In 2014, there was a midterm election, of course, with different national dynamics and turnout patterns than a presidential election. But we do not know, obviously, how the presidential contest in this era of relatively high straight-ticket voting will affect Senate races. We do know that five of the last six presidential elections were barn burners reflecting the relatively even partisan divide that voters again confirmed in 2022. There is no particular reason to think that 2024 will be a landslide in either direction.
There are obviously other variables affecting Senate races that we cannot at present anticipate. Highly competitive Senate primaries in blue or red states like California and Indiana could either produce rare opportunities for the minority party or simply soak up campaign cash better deployed elsewhere.
But right now, Democrats have their work cut out for them in holding on to the Senate beyond January 3, 2025. That matters a great deal if Biden wins a second term and needs the Senate to confirm his nominees — or if Trump or someone worse wins the presidency and Republicans hang on to the House.
