Analysis: Senate tilting red, House blue for 2024

The possibility of a split congressional decision in 2024, with the Senate flipping to Republicans and the House turning over to Democrats, is looking increasingly likely.

Why it matters: By pursuing an impeachment inquiry into President Biden, House GOP leaders are making life awfully tough for their 18 vulnerable Republicans representing Biden 2020 districts. Threats of a government shutdown from GOP hardliners don’t help either.

• Meanwhile, Biden’s persistently low approval ratings are making it very difficult for red-state senators vying for re-election — West Virginia’s Joe Manchin, Montana’s Jon Tester and Ohio’s Sherrod Brown — to win enough split-ticket voters at a time of record polarization.

By the numbers: To win back control of the Senate, Republicans only need to net two seats (one if the GOP presidential nominee prevails).

• The 2024 Senate map is historically favorable for Republicans: Republicans are aggressively contesting at least eight Democratic-held seats with Democrats hoping — in a best-case scenario — of putting Sen. Ted Cruz’s Texas seat in play.
• But House Republicans are in an equally precarious position. To win back control of the House, Democrats only need to flip a net five seats. A new House race analysis from Inside Elections (subscription) rates 11 seats as toss-ups — seven held by Republicans, and four by Democrats.

The big picture: With national polarization near all-time highs, most voters are casting straight-party ballots.

• There are only five senators representing states carried by the opposing party’s presidential candidate. Of those, the only ones up for re-election in 2024 are the three vulnerable Democratic senators mentioned above.
• There are currently only 23 lawmakers (18 Republicans, 5 Democrats) representing House districts carried by the presidential candidate from the opposite party.
• That means House Republicans face a whole lot more exposure than Democrats unless their swing-district members can create ample distance from their party’s leadership.
• Nine of the 18 Biden-district Republicans are freshmen who outperformed Trump by at least five points in last year’s election. As a sitting lawmaker, convincing voters of your independence is more difficult when you have a voting record in Congress — especially with the higher turnout of a presidential election year.

Between the lines: House GOP and Senate Democratic leaders are employing two strategies to protect their most vulnerable members.

• House GOP leaders have encouraged unity within their conference, with Speaker Kevin McCarthy (R-Calif.) trying — often awkwardly — to find a middle ground that can satisfy both the pragmatists and the hardliners.
• It’s notable that politically vulnerable House Republicans haven’t spoken out against the pursuit of an impeachment inquiry against Biden, even though they’ll need to win over Biden voters to secure re-election.
• By contrast, Senate Majority Leader Chuck Schumer (D-N.Y.) is content to let his red-state senators demonstrate some independence from the White House (at least in an election year). Manchin is openly feuding with Biden, while Tester joined with Republicans to block the confirmation of Biden’s nominee for Labor secretary.

Reality check: Candidates still matter, despite the surge in partisan voting behavior.

• The reason Senate Republicans have been active in endorsing preferred candidates against Manchin and Tester is that they recognize those Democrats have a track record in winning crossover votes — typically because of weak GOP challengers in the past.
• House Democrats are also facing recruitment questions in several battleground districts where the leading candidates are to the left of a typical swing voter — and where crowded primaries could get messy.

• House Republicans have a few recruitment challenges of their own against a handful of the Democrats representing Trump districts, where the losing GOP candidate from 2022 is seeking a rematch.

Driving the news: House Democrats have been getting favorable news on the redistricting front, with court decisions boosting their chances of picking up a seat in three Southern states: Alabama, Florida and Louisiana.

• Democrats also have a reasonable chance of netting several additional seats if New York is ordered to redraw its congressional lines for 2024. The case will be decided later this year.
• On the flip side, Republicans are expected to gain several seats from North Carolina’s GOP-controlled redistricting.

Zoom in: Republicans and Democrats are tied on the congressional generic ballot at 44%, according to RealClearPolitics’ polling average, with polls showing both parties are viewed unfavorably by most voters.

• Biden and Trump are also virtually tied — Trump at 45.6%, Biden at 45% — in the RCP polling average.

The bottom line: The country is deeply divided, which foreshadows the likelihood of split government continuing past next year.

• Political sentiment has remained remarkably stable over the last year — even in light of major political developments, like Trump’s indictments. That’s unlikely to change heading into 2024.
• All politics is now national. That makes the fundamentals as significant as ever: A favorable map gives Senate Republicans an early edge, and House Democrats a slight advantage. The battle for the presidency, meanwhile, looks like a pure toss-up.
• But if Biden, Trump (or any GOP opponent) pulls away in the presidential race, there’s a good chance they’ll hand their party the House majority as well.