The Senate looks like a jump ball. Here are the 10 seats that will decide the majority

At this point, control of the U.S. Senate next year looks like a jump ball.

Four months ago — the last time we wrote about the top 10 seats most likely to change hands — Republicans were growing confident they would win the chamber.

But a lot has changed in that time.

The Supreme Court's overturning of Roe v. Wade has boosted Democratic enthusiasm (and fundraising); a handful of hardline or untested Republican challengers won their primaries; and the Jan. 6 committee hearings and the FBI search of former President Donald Trump's Florida home have put him front and center yet again, threatening to make the election a choice rather than a referendum on President Biden and Democratic governance.

Senate Minority Leader Mitch McConnell noted last week that "candidate quality" could hamper Republicans' ability to win the chamber.

"I think there's probably a greater likelihood the House flips than the Senate," the Kentucky senator said in his home state. "Senate races are just different, they're statewide. Candidate quality has a lot to do with the outcome."

It's all giving Democrats hope of retaining the 50-50 Senate, which they narrowly control with Vice President Harris casting tie-breaking votes. But inflation remains the top concern for many voters, especially independents, and Biden continues to be unpopular — though many Democratic candidates are outperforming his approval.

Here's where things stand in the key races, in order of most likely to flip:

1. Pennsylvania (Previous: 1)
2. Georgia (Previous: 2)
3. Arizona (Previous: 5)
4. Nevada (Previous: 3)
5. Wisconsin (Previous: 4)
6. New Hampshire (Previous: 6)
7. North Carolina (Previous: 7)
8. Ohio (Previous: 8)
9. Florida (Previous: 9)
10. Colorado (Previous: 10)

1. Pennsylvania (R-Open)

Democrat John Fetterman has held up well so far against Trump-backed TV doctor Mehmet Oz, despite suffering a stroke that kept him off the campaign trail for months. Fetterman is better liked, and he's pounded Oz's residency and wealth on social media. Oz, on the other hand, is coming off a bruising primary and hasn't quite found his footing.

Still, Oz is in striking distance. For him to improve his odds, he will need to pierce Fetterman's brand, as Republicans try to figure out the best issue set to stick to Fetterman. Some operatives believe it's not tying the tough-talking, burly former mayor to left-wing politics, like Medicare for All or the democratic socialism of Sen. Bernie Sanders, but fracking and crime. So far, that message hasn't taken hold.

2. Georgia (D-Warnock)

Very little separates the next four races, which are all expected to be extremely tight.

Georgia has remained close, and incumbent Democratic Sen. Raphael Warnock has done well so far. Republicans acknowledge that earlier efforts to try and paint Warnock as a "radical" were a mistake. It's tough to make the pastor at Ebenezer Baptist Church — the same post once held by Dr. Martin Luther King Jr. — whose ads have featured him smiling with a beagle, look like a bad guy. Instead, the attacks to come are more likely to be simply making Warnock out to be a Democrat whose votes are out of step with Georgia.

But Georgia is about as purple as it comes now, and Warnock's Trump-backed opponent, Herschel Walker, has his issues as a candidate. Still, the former NFL and University of Georgia running back has high name ID and appeal among Republicans. And Walker will likely benefit from the gubernatorial race of Republican Brian Kemp, who is currently favored to win reelection. This one will likely be a nail-biter.

3. Arizona (D-Kelly)

Incumbent Democrat Mark Kelly has a lead in the polls and has struck a moderate profile in this state Biden won narrowly. Plus, Trump-endorsed Republican Blake Masters won his primary and backs Trump's election lies. But this is Arizona, and operatives in both parties expect this race to tighten. Masters has landed in controversy on multiple topics, but Democrats have chosen to focus on his hardline stance on abortion. In fact, one of the first ads run against him after the primary was on that, showing what a salient issue Democrats think it is, especially with independents, which are so crucial in this state.

But Republicans see inflation and immigration as the two most important issues. Plus, Masters is already making a tonal shift now that he's in the general election. Republicans also outnumber Democrats in the state by about 147,000, and with a third of the state not identifying with either party, independents are key for Kelly. Democrats have been able to win over independents in recent Senate elections in the state, but it's a tougher task in the first midterm of an unpopular Democratic president.

4. Nevada (D-Cortez Masto)

Nevada's political leaning and demographics — with substantial Latino and Asian American populations — tend to favor Democrats. But Republicans continue to doubt the strength of incumbent freshman Catherine Cortez Masto's candidacy.

Democrats, on the other hand, think Cortez Masto, the first Latina elected senator, has run a good campaign so far, focusing on local issues, like helping get drought funding in the Democratic-passed Inflation Reduction Act.

Democrats outnumber Republicans in Nevada by tens of thousands of voters, and Democrats think abortion will fire up their voters to head to the polls. Republican Adam Laxalt is a controversial candidate who has backed Trump's election lies, but he is a former attorney general who is also a political scion in the state. (His grandfather, Paul Laxalt, was a senator and governor.)

5. Wisconsin (R-Johnson)

Incumbent Republican Sen. Ron Johnson is not very well liked in the state and has landed in numerous controversies related to the coronavirus vaccine and his ties to Trump and the Jan. 6 insurrection. Johnson hardly cuts the image of the vanilla businessman that helped him first win his seat in 2010. An early poll shows he could be in trouble, but Republicans are feeling positive about his chances. They say Johnson is doing a good job raising money and running a strong campaign, doing the groundwork, even reaching out to the small share of Latinos in the state.

The Democrat here is Lt. Gov. Mandela Barnes, who is less well known, though he has won statewide. While Democrats want to make this about Johnson, Republicans will seek to paint Barnes as progressive as anyone in the state, particularly on crime and ties to the "defund the police" and "defund ICE" movements, which he has tried to distance himself from in recent months.

6. New Hampshire (D-Hassan)

This is the one key Senate race that doesn't have its general election matchup set. That would be thought of as an advantage for incumbent Sen. Maggie Hassan, but New Hampshire is a purple state with a strong independent and libertarian streak, and Hassan's numbers have lagged. Biden may have won New Hampshire in 2020 by 7 points, but he's now very unpopular in the state. That makes it a tough place for a Democrat up for reelection.

The GOP primary will be decided Sept. 13, and no candidate has really stood out from the pack. So far, Don Bolduc, a retired Army general who has backed Trump's election lies and whom Trump has praised, has a lead in polls over the more staid state Senate President Chuck Morse and others. Primary polls have moved quickly this year closer to elections, and this race hasn't gotten a lot of attention yet, but Republicans likely would rather make this a campaign between a more generic Republican and Hassan rather than with an election denier.

7. North Carolina (R-Open)

These next two are close, but still lean in Republicans' direction.

Democrats like what they've seen out of their nominee in North Carolina, Cheri Beasley, the first Black chief justice of the state Supreme Court. That's a statewide elected position, one she lost by just 401 votes out of more than five million in 2020. (Biden lost the state by more than 100,000 votes.)

Notably, she has more than doubled the amount of money raised by Republican Rep. Ted Budd, the Trump-endorsed candidate, as of June 30. North Carolina has a Democratic governor, as well, but this has been something of a Lucy-and-the-football state for the party. Democrats have been close, but won no presidential or Senate races since Barack Obama (and former Sen. Kay Hagan) won in 2008.

There are more Democrats in the state than Republicans, but independents here are more GOP-leaning, which has given Republicans the advantage in recent federal elections. What's more, while Republicans have seen their ranks stay about the same since 2020, Democratic registrations have shrunk since then, when Biden lost by 1.4 points.

8. Ohio (R-Open)

Democratic Rep. Tim Ryan has run a strong, middle-of-the-road campaign so far, Democrats say. And it's showing in the polls against Republican J.D. Vance, who has landed in controversies with his remarks on women and family. Vance has a lot of work to do to right his campaign's ship. He's been seen as running a weak campaign and Ryan has raised seven times the amount of money as Vance.

But there's a long way to go. And the cavalry is about to come to Vance's aid. The Senate Leadership Fund is planning to plunk down $28 million to boost Vance, more than quadrupling what Republicans have already spent on his candidacy. Plus, this is a Republican-leaning state that Biden lost by 8 points. The president's approval rating is underwater in the state, and Ryan has distanced himself from Biden.

9. Florida (R-Rubio)

Rounding out the top 10 are two states that are stretches for both parties, but where they are competing strongly.

In Florida, Republican incumbent Marco Rubio has veered a long way from his 2016 anti-Trump days that won him the pejorative "Little Marco" from Trump. Since then, he's shrunk into the former president's shadow, denouncing the search at Trump's Florida home, for example, as a "Third World Act."

The fact is: Rubio needs Trump's supporters in a state Trump won twice and where conservative Ron DeSantis is governor. Challenging him is Democratic Rep. Val Demings. Demings, a former Orlando chief of police, was a Trump impeachment manager and has actually outraised Rubio, highly unusual for a sitting senator. At the end of the day, though, this is still Florida, and Republicans outnumber Democrats by more than 200,000 voters.

10. Colorado (D-Bennet)

The incumbent here is Democrat Michael Bennet. Republicans are happy their candidate Joe O'Dea, a more moderate construction company executive who supports abortion rights in the early months of a pregnancy, made it through the primary against an election denier who did not believe in any exceptions for abortion. (Trying to get through the primary, O'Dea touted on his website that "pro-lifers" had endorsed him.)

Democrats aim to use abortion to fire up their voters in this state, where Democrats outnumber Republicans by about 100,000 voters. They'll paint O'Dea as a vote for McConnell for majority leader and the 51st vote to ban abortion — despite the fact that O'Dea has said he would vote to codify early-term abortion rights and later with exceptions. (He has likened himself to a "Republican Joe Manchin.")

Republicans don't believe Bennet has been pushed and think he's potentially vulnerable. He won in 2016 with just 50% and by 6 points. (Republicans also believe they can give Sen. Patty Murray in Washington state a run for her money, but that hasn't borne out so far and is an even more left-leaning state than Colorado.)

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