Georgia Senate runoff is really important to Democrat Senate math in 2024

Democrats came out on top in this year’s Senate election — but that was the easy part.

The hard part comes in 2024, when the party is faced with an extremely unfavorable map that could put it in a deep Senate hole for some time if things go even slightly bad.

Even though next week’s runoff election pitting Sen. Raphael Warnock (D-GA) against Herschel Walker (R) won’t determine next year’s Senate majority because Democrats have already won it, its outcome will have a significant impact on that how well positioned the party is in its next very challenging Senate cycle.

Currently, only three Democratic senators represent states won by Donald Trump in 2020, and they all are up for re-election in 2024. These are Joe Manchin (D-WV), Jon Tester (D-MT) and Sherrod Brown (D-OH). ), although only Brown has confirmed he’s walking again. These are all very red states and will be quite difficult for the Democrats to win in a presidential year.

But the vulnerabilities run deeper. The only remotely close states in the presidential race where Republicans are defending seats are Florida and Texas — two states where Democrats have been falling short of late. Democrats are also defending seats in five states that Joe Biden won very narrowly in 2020. These seats will be held by Kyrsten Sinema (D-AZ), Tammy Baldwin (D-WI), Bob Casey Jr. (D-PA), Jacky Rosen (D-NV) and Debbie Stabenow (D-MI).

Democrats might think they don’t need to worry about that seating arrangement, because the party just defied the naysayers in a tough 2022, winning at least one statewide contest in every one of them — that’s how clearly these states lean in their favorites.

But it’s always a mistake to overlook the results of the last election and underestimate how much could change by the next. In particular, if Trump is not re-nominated, party coalitions could be thrown into unpredictable disarray. And even Trump came pretty close to winning those states in 2020.

The class of 2024

Senators serve six-year terms, leaving only one-third of the panel up for election each cycle. And the particular grouping of Senate seats (referred to as “classes”) up for grabs in 2024 has had a particularly appealing run for Democrats. For a strong Republican performance, you have to go back to the 1994 GOP wave. Since then they have been on the ballot in the following years:

  • 2000: A hard-fought presidential year, with Al Gore winning the popular vote, but George W. Bush winning the Electoral College and Democrats winning four Senate seats on the net
  • 2006: A year of the Democratic Wave in which the party recaptured both the House and Senate, gaining six seats in the latter chamber
  • 2012: A strong Democratic year for Barack Obama’s re-election, in which the party unexpectedly increased its Senate majority by two seats
  • 2018: Another year of the Democratic wave — but the party had won so many deep-red state seats in previous cycles that it had multiple incumbents in heavily Republican territory, ending up with a net loss of two seats

So this Senate class is risky for Democrats in part because they’ve had so much luck with it in the past. Almost half of the Democratic Senate majority — 23 incumbent senators — come from this seat, so they’ll all be up for election in 2024. Meanwhile, only 10 Republicans will run, although special elections could increase that number. That’s a numerical disadvantage. However, the downside extends to which specific seats are up.

Which specific places are free

To understand the magnitude of the challenge facing Democrats, it’s important to recognize that the Senate has changed. In the past, it was common for a state’s voters to support Senate and presidential candidates from different parties. For example, after the hotly contested 2000 election, 30 out of 100 incumbent senators represented states where their party’s presidential candidate had not won the last election. That’s a lot of ticket splitting.

Since then, that number has gradually declined as red-state Democrats and blue-state Republicans have retired or suffered defeat. When Trump took office, there were 14 such senators left. Next year it will be either five or six (depending on whether Walker can unseat Warnock in the Georgia runoff). The Senate sorted by partisanship.

Of course, very close states can still go either way in the presidential race. But defying partisan gravity in deeply Republican or Democratic states has become much more difficult — especially in a presidential year. In 2016, zero states elected presidential and senate candidates from various parties. In 2020, only one state did, as Republican Sen. Susan Collins and Joe Biden both won in Maine.

In 2024, all three Democratic senators representing the states Trump won in 2020 — Manchin in West Virginia, Tester in Montana, and Brown in Ohio — are in office.

A chart showing Democrats have 23 Senate seats to choose from in 2024.  Three are in states that Trump won by a wide margin in 2020, and another five are in hard-fought swing states.

Andreas Prokop/Vox

Manchin and Tester have not announced if they are running again. Both have won repeatedly in their respective states, although their wins in 2018 were close (each winning by about 3.5 percentage points). If one or both resign, Democrats would have tremendous difficulty finding candidates with comparable bipartisan appeal. Brown has said he’s running again, and Ohio isn’t quite as red as the other two states, but if Republicans can find a competent challenger, he’ll face stiff competition, too.

So that’s three seats that Democrats are going to have a hard time getting in based on underlying partisanship alone.

Then there are five swing states that, if recent history is any guide, likely align closely with Senate and Presidential findings.

In Arizona, Kyrsten Sinema has infuriated the progressives and could face a major challenge from Rep. Ruben Gallego. In Nevada, Jacky Rosen just watched her colleague Catherine Cortez Masto narrowly escape a very close competition in 2022. Then there are the popular Rust Belt incumbents Debbie Stabenow, Tammy Baldwin and Bob Casey Jr.

None of them will start out as underdogs, and all might well survive. But again, a lot will likely depend on the presidential contest, and if that contest veers toward the GOP, more of those Senate seats could follow.

Next is a list of likely Democratic states – Maine, where Independent Senator Angus King meets with the Democrats; he is 78 and has not yet announced if he is running again, Minnesota (Amy Klobuchar), Virginia (Tim Kaine) and New Mexico (Martin Heinrich). All start as favorites, but these states are not so overwhelmingly democratic that they would absolutely win.

In addition, Democrats must also defend the seat of Sen. Bob Menendez (D-NJ), who is under renewed federal investigation. Menendez had previously been charged with public corruption in 2015, but his trial ended in a hung jury and the Justice Department dropped the case. New Jersey is a solid Democratic state, but the party would probably feel better if their nominee wasn’t a constant target of the DOJ.

Meanwhile, of the GOP-held seats up for election, only Sens. Rick Scott (R-FL) and Ted Cruz (R-TX) are in distantly nearby presidential states.

A chart showing Republicans holding just 10 Senate seats in 2024, and they all sit in states Trump won in 2020.

Andreas Prokop/Vox

Florida has turned its back on the Democrats, as seen in the recent landslide reelection victories of Governor Ron DeSantis and Senator Marco Rubio this month. Texas is leaning towards the Democrats (Trump won it by just 5.6 percentage points in 2020 and Cruz won re-election by 2.6 percentage points in 2018), yet the Democrats have not won a statewide race there since 1994.

take that away

Democrats’ 2024 ban on Senate math raises the stakes in Georgia’s Warnock/Walker runoff — if the party starts with a 51-49 majority instead of a 50-50 majority, they can at least afford to have one next cycle Losing your seat without losing control.

That’s especially important because the party’s biggest challenge in a presidential year will be retaining its three seats in the deep red states of West Virginia, Montana and Ohio. The first big question is whether Manchin and Tester will run again, and if they do, the next question is whether they can defy partisan gravity like Collins did in 2020.

But an analysis based solely on national partisanship would suggest that even in a great year for their presidential nominee and their party nationally, the Democrats are likely to lose all three seats. That’s the main reason why it will be so difficult for them to hold the Senate. The Senate’s 2022 map was, as I wrote last year, “relatively balanced,” but the 2024 map just isn’t. (And again, that’s largely because the Democrats have been so successful in these races before that they just have more to lose.)

What if 2024 isn’t a good year for Democrats nationally? Well, then they could lose some or all of those five swing seats of state, making them a serious Senate deficit that could take many years to get out of.