Why Republicans are likely to win the Senate this year

The race for the White House hogs most of the attention in a presidential election year, relegating the race for Congress to ugly stepsister status.

But in recent years, we’ve all learned how important down-ballot races can be in shaping American policy. That’s especially true for the Senate, which is responsible for the confirmations of government officials and Supreme Court nominees.

In this year’s battle for the Senate, like so many cycles before, we have the same competing forces: The election fundamentals favor Republicans, while candidate quality appears to favor Democrats, who currently hold a narrow majority in the chamber.

For now, though, it appears even flawed Republican candidates likely won’t be able to stop their side from winning Senate control.

Democrats face two “M” problems: the math and the map.

Let’s start with the math. Republicans need a net gain of one seat to win the Senate if Donald Trump wins the presidency (with his vice president casting any tie-breaking votes). They need a net gain of two seats for a majority regardless of who wins the presidential election.

Republicans have a lot of options to net those one or two seats. Senate Democrats (including independents who caucus with them) hold 23 seats up for election this year; Republicans hold 11.

This brings us to the map.

Eight of the 23 Democratic seats up for election this year are in states either where Trump won in 2016 or where he is up by at least 5 points in the polls now. Five of them are in states where Trump holds at least a 5-point advantage. Three are in states where Trump won by at least 8 points in 2016 and 2020 and where the incumbent senator is the only Democrat in nonjudicial statewide office.

One of those three is West Virginia, where Democratic Sen. Joe Manchin is retiring. Trump won the state by 39 points in 2020, and every respectable nonpartisan handicapping outlet views the seat as a safe Republican pickup.

There are only two Republican Senate seats being targeted by Democrats – Florida and Texas, which Trump carried by single digits in 2020. But the GOP incumbents in both states currently lead their Democratic opponents by double digits.

Every other Republican-held Senate seat on the ballot this year is in a state where GOP presidential candidates have dominated since 2012.

It’s no wonder that my colleague Simone Pathe had only one Republican seat (Texas) on her most recent list of the 10 Senate seats most likely to flip this year, and that was at No. 10.

Positive signs for Democrats

But is the race for the Senate really over if Republicans just win West Virginia?

No, we can’t call it just yet, and it’s not just because we’re still months before the general election. It’s because if President Joe Biden does win – a real possibility – it’s not entirely clear which second Senate seat Republicans will pick up to gain control.

Among the eight Democratic Senate seats mentioned above, there are no states beyond West Virginia where the polls (or expert judgment) show Republicans with a solid lead, despite the fundamentals favoring their party this year. Democratic Senate candidates seem to be at least tied or ahead in Arizona, Michigan, Montana, Nevada, Ohio, Pennsylvania and Wisconsin.

The Democratic Senate candidates’ margins outran Biden’s in the four states – Arizona, Nevada, Pennsylvania and Wisconsin – that The New York Times and Siena College recently polled. And we’re not just talking by a little bit; we’re talking about them doing better than Biden by at least 5 points in those four states among likely voters.

A key reason the Democratic candidates are doing so much better than Biden is because they’re popular. We know from recent polls that Sens. Bob Casey of Pennsylvania and Tammy Baldwin of Wisconsin had positive net favorability ratings, while Biden’s numbers were well under water in these states.

Meanwhile in Arizona, Republicans appear poised to nominate Kari Lake for Senate. Lake was last seen losing a very winnable gubernatorial election in 2022 and her high unfavorable score with state voters was a big reason why Inside Elections recently shifted its rating of the race in the Democratic direction.

Of course, Democratic Senate candidates outrunning the top of the ticket is nothing new. Republicans have memorably lost plenty of very winnable seats over the past decade and a half with bad candidates (see 2010 with Nevada’s Sharron Angle and 2012 with Missouri’s Todd Akin).

Two years ago, Republicans had a net loss of one Senate seat as Democrats retained control of the chamber in a midterm election when Biden had approval ratings in the low 40s. Again, the GOP ran several unpopular candidates (e.g., Mehmet Oz in Pennsylvania), while Democrats ran relatively popular ones (e.g., Mark Kelly in Arizona)

Back to the math and map

Still, it’s hard to ignore Republicans’ advantage in 2024 with the math and the map. Senate Democrats have no margin for error, and they are unlikely to win all seven of their seats currently seen as competitive.

The past two presidential cycles tell the tale: Just one state (Maine in 2020) voted differently in the presidential and Senate races.

Trump likely holds a comfortable polling advantage of at least 5 points over Biden right now in Arizona, Nevada, Montana and Ohio. His lead in Montana is likely in the double digits. Putting aside the polls, Montana and Ohio were not competitive on the presidential level in either 2016 or 2020 and likely won’t be this fall.

For Democrats to have any chance of holding the Senate, Republicans would have to lose all these Senate races. Then they’d have to lose in Michigan, Pennsylvania and Wisconsin – all states that Trump could very well win again.

Republicans would also have to lose in Maryland – where Biden will almost certainly win in a blowout, but where GOP former Gov. Larry Hogan has been competitive in the polling.

Republicans may be prone to blowing it when it comes to Senate races. But I’m not even sure the Washington Generals of Senate races can blow this one.

As a memorable “Simpsons” episode once put it, Republicans may finally be “due.”

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