(The Hill) — Democrats are fighting tooth and nail to hold onto their ultra-narrow Senate majority this year, in a midterm election cycle that has several of the party’s incumbents looking vulnerable because of rising inflation, particularly surging gas prices.

Republicans need to net just one new seat this year to reclaim control of the upper chamber. Still, Democrats are more optimistic about their chances of holding their Senate majority than they are their House majority, and are eyeing several opportunities to flip GOP-held seats.

Here are the seven Senate seats most likely to flip in November:

Pennsylvania

Sen. Pat Toomey’s (R-Pa.) retirement and President Joe Biden’s narrow victory in the Keystone State in 2020 have transformed Pennsylvania into perhaps the most competitive battleground of the midterm elections, offering Democrats one of few opportunities this year to take control of a GOP-held Senate seat.

Democrats have coalesced around Lt. Gov. John Fetterman’s Senate bid. He easily won the party’s nomination last month, beating out his main rival Rep. Conor Lamb (D-Pa.) by a 32-point margin. 

Former President Donald Trump’s endorsed candidate, celebrity physician Mehmet Oz, clinched the Republican nomination, but only after a recount. Ultimately, he defeated his top primary opponent, former hedge fund CEO David McCormick, by fewer than 1,000 votes.

The race between Fetterman and Oz is still in its infancy, but a USA Today Network/Suffolk University poll released this week showed the Democratic lieutenant governor leading by a 9-point margin. But Fetterman and his party are facing a difficult political environment this year, and there’s still time for Oz to solidify his support among Republican voters.

Georgia

Sen. Raphael Warnock (D-Ga.) pulled off a major victory last year, beating out former Sen. Kelly Loeffler (R-Ga.) in a hotly contested runoff election that helped Democrats reclaim the Senate majority.

Holding onto his seat this year, however, is likely to prove more challenging. Democrats are up against strong political headwinds nationally and his Republican rival, former football star Herschel Walker, faced little serious opposition in the state’s May 24 Senate primary.

Both parties are already spending heavily to win the Senate seat in Georgia, and early polling in the general election suggests an ultra-tight race. A survey from Eastern Carolina University released this week showed Warnock and Walker tied at 46 percent. 

Warnock has a major financial advantage in the race; his latest federal filing shows him with nearly $23 million in the bank to Walker’s $7.1 million. But Georgia’s status as a political battleground is still relatively new, and Republicans believe that the state stands a good chance of swinging back in their direction this November.

Nevada

Sen. Catherine Cortez Masto (D-Nev.) is set to face off against former state Attorney General Adam Laxalt in November after the Trump-endorsed candidate clinched the GOP nomination this week. 

While Cortez Masto is an adept campaigner in her own right — she’s a former chair of the Democratic Senatorial Campaign Committee (DSCC) and a political mentee of the late Senate Majority Leader Harry Reid (D-Nev.) — she’s also facing a tough environment in a state that in many ways epitomizes some of the biggest challenges facing Democrats this year.

Nevada has some of the highest gas prices in the country and the state’s economy, which depends heavily on tourism, took a hit as the COVID-19 pandemic prompted shutdowns of hotels, bars and restaurants. 

At the same time, the Senate race in Nevada is expected to test Democrats’ resilience among Latino voters, who make up a significant share of the state’s electorate. While those voters have long been a key Democratic constituency, there have been signs in recent years that that may be starting to change. 

Arizona

Sen. Mark Kelly (D-Ariz.) narrowly ousted former Sen. Martha McSally (R-Ariz.) in a 2020 special election, winning a Senate seat that hadn’t been held by a Democrat in more than 50 years.

Now, he’s running for his first full term in the upper chamber. And while he has the fundraising chops and personal narrative of a top-tier candidate, he’s facing voters in a much different political environment than he did two years ago. 

Of course, Kelly has the advantage of incumbency and isn’t facing any primary opposition. Meanwhile, half a dozen Republicans are vying for their party’s Senate nomination, including state Attorney General Mark Brnovich, businessman Jim Lamon and venture capitalist Blake Masters, who scored Trump’s endorsement earlier this month. 

Sespite the fact that Democrats currently hold both of Arizona’s Senate seats, the state is far from a Democratic stronghold. Early polling shows Kelly outperforming his top Republican challengers in hypothetical head-to-head matchups. Still, it’s a tough political climate for Democrats and a motivated GOP voter base this fall could turn the tables on him.

Wisconsin

Outside of Pennsylvania, the Senate race in Wisconsin is one of Democrats’ best chances of flipping a Republican-held seat.

Sen. Ron Johnson (R-Wis.) is vying for a third term in the Senate despite previously pledging to only serve two terms. He’s also a universally despised figure among Democrats, who are hoping that his penchant for controversy can help propel them to victory in November.

The Wisconsin primaries are still nearly two months away, but the top candidates vying for the Democratic Senate nomination are Lt. Gov Mandela Barnes, state Treasurer Sarah Godlewski, Milwaukee Bucks executive Alex Lasry and Outagamie County Executive Tom Nelson. 

Of course, while Johnson is a polarizing figure nationally, he’s shown an ability to make it through tough elections before, defeating former Sen. Russ Feingold (D-Wis.) twice, in 2010 and 2016.

New Hampshire

On the surface, New Hampshire is the Senate battleground that offers Democrats perhaps their best chance of holding a seat. Biden carried the state in 2020 by a 7-point margin after Sen. Maggie Hassan (D-N.H.) narrowly ousted incumbent Sen. Kelly Ayotte (R-N.H.) four years earlier.

Republicans were also dealt a blow last year when Gov. Chris Sununu (R) opted against a Senate bid, leaving a crowded primary field to duke it out for the nomination. Among the Republicans running are state Senate President Chuck Morse, former Londonderry town manager Kevin Smith and retired Army Brig. Gen. Don Bolduc.

Nevertheless, Hassan won her last election by only about 1,000 votes and, like Democrats across the country, is facing a challenging political environment in a state that has a penchant to swing between parties. 

One advantage she has, however, is time. The New Hampshire primaries won’t be held until mid-September, meaning it will be months before Republicans will know who their nominee is.

North Carolina

North Carolina may be a perennial battleground, but Democrats have had a tough go of it in the state in recent years. Trump carried it twice and Democrats were dealt a frustrating defeat in 2016 when their Senate nominee Cal Cunningham lost to Sen. Thom Tillis (R-N.C.) following embarrassing revelations of an extramarital affair.

This year, however, no candidate will have the incumbent advantage that Tillis had. Sen. Richard Burr (R-N.C.) is not seeking reelection. Rep. Ted Budd (R-N.C.), whom Trump endorsed last year, emerged from the state’s May 17 GOP primary, while former state Supreme Court Justice Cheri Beasley (D-N.C.) easily clinched the Democratic nod.

Democrats see Beasley as an ideal pick for the seat. If elected, she would be the first Black U.S. senator from North Carolina. And she’s won statewide races before. 

But flipping Burr’s seat won’t be easy. Republicans have largely rallied around Budd as their nominee and he has the backing of GOP power players, including the conservative Club for Growth, which spent millions of dollars to boost him in the primary.