Though more Republican-held seats are up for grabs in November, Democratic struggles mean the GOP has improved its likelihood to take control of the Senate. Here are the key contests to watch.

Transcript

DANIEL ESTRIN, HOST:

The first U.S. Senate primaries are just weeks away. Republicans are aiming to take back the chamber, which is split 50-50, but under control of Democrats who have the vice president's tie-breaking vote.

NPR's senior political editor and correspondent Domenico Montanaro is here to tell us what Senate races he's watching as primary season heats up. Hi, Domenico.

DOMENICO MONTANARO, BYLINE: Hey, Daniel.

ESTRIN: Who has the advantage here?

MONTANARO: Well, right now, Republicans do. You know, inflation and other issues have really taken a bite out of President Biden's political standing. And first midterms are always tough for a president's party. You know, Democrats started out with a pretty favorable map, actually, at the outset of this. In fact, the top handful of states are places Biden won in 2020, but they were all very close and all Republicans really need is a light breeze in their direction to take control.

ESTRIN: Huh - OK, so let's get to your map. What are those top states that you're looking at?

MONTANARO: Well, Senate control is basically playing out in six states - Pennsylvania and Wisconsin, which are the two Democratic targets and Georgia, Nevada, Arizona and New Hampshire, which are Republicans' best chances to flip control.

ESTRIN: Yep, those all sound like the familiar swing states from the presidential elections. So let's talk about those places Democrats are keying in on first.

MONTANARO: Well, Pennsylvania tops the list. You know, hundreds of millions of dollars are going to be spent there. Tens of millions have already been spent, mostly in the Republican primary so far. This is a seat that came open with the retirement of Republican Senator Pat Toomey. Former President Trump endorsed TV celebrity Dr. Mehmet Oz over the weekend, but he's locked in a tough fight with David McCormick, who used to be a Hedge Fund Manager and is spending a lot of his own money on this race. The winner is expected to face the Democratic Lieutenant Governor, John Fetterman. He's a blue-collar progressive, but he looks more like a pro wrestler, frankly. And this will no doubt be an entertaining one to watch.

In Wisconsin, Republican Ron Johnson is the most vulnerable Republican senator up for re-election. He's a staunch Trump ally and antagonist of the left. He survived a tough race in 2016. He's no doubt in for another one this time.

ESTRIN: OK, so how about Republicans? Because we know Georgia has been a hotbed of political activity in recent years.

MONTANARO: Yeah, no doubt about it. I mean, Biden won there in 2020 by a razor-thin margin. Since then, his approval in the state, though, has nosedived. That's made it tough for freshman Democratic Senator Raphael Warnock.

But Georgia's another example of untested Republican candidates with checkered pasts that Trump is throwing his weight behind. Think about Dr. Oz in Pennsylvania. In Georgia, the likely Republican nominee is Herschel Walker, the former NFL running back. But Walker is facing domestic abuse allegations from past relationships, and there are questions about his financial record after football.

ESTRIN: Whoa, that sounds like it'll get a lot of attention.

MONTANARO: It will. But Republicans actually privately say, look toward Nevada. They believe that is their best chance to flip a seat. Nevada often gets overlooked, but elections there are always close. Democratic incumbent Catherine Cortez Masto has cut a low profile in Washington. In an off-year election, Democrats have to worry about turning out Latinos and Asian American voters who are so key there and have showed some signs of frustration with Democrats. She has the money advantage. Her likely opponents - Adam Laxalt, a former state attorney general, close to Trump and an election denier.

Republicans also having a couple of recruiting difficulties - couldn't convince Arizona and New Hampshire governors to get into the race. So it's not all a cakewalk for them, but they're growing confident that these candidates will be pushed over the finish line at the end of the day and they'll control the Senate.

ESTRIN: Thanks Domenico.

MONTANARO: Hey, you're welcome.

ESTRIN: That's NPR's Domenico Montanaro. Check out his full analysis of the 10 Senate races most likely to flip at npr.org.

(SOUNDBITE OF MUSIC) Transcript provided by NPR, Copyright NPR.

Correction

An earlier version of this story said that Sen. Raphael Warnock is a former pastor at Ebenezer Baptist Church. He is still pastor there.