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The 10 Senate seats most likely to flip

(CNN) The passage of a sweeping infrastructure plan in the Senate on Tuesday gives both parties plenty of ammunition heading into a midterm campaign season -- look no further than the most competitive Senate seats for how that will play out.

Democrats are on offense in six of the 10 top races; they're trying to flip those red seats blue, and they'll be pointing to the $1.2 trillion package as a shining example of what Democratic control can deliver for the American people, while some GOP candidates attack it for spending too much money.

One of Democrats' top targets -- Pennsylvania -- remains the seat most likely to flip. The top 10 Senate seats most likely to flip are based on CNN's reporting and fundraising data, as well as historical data about how states and candidates have performed. As the cycle heats up, polling and advertising spending data will also become factors. Our ranking first published in March, and was updated in April, May and July.

President Joe Biden carried Pennsylvania in 2020 after former President Donald Trump narrowly carried it in 2016, and it's now an open seat since GOP Sen. Pat Toomey is not running for reelection. Toomey, a former president of the Club for Growth first elected to the Senate in 2010, voted against the infrastructure bill, calling it "too expensive, too expansive." The bill passed 69-30 with 19 Republicans joining with Democrats.

Most of the other GOP senators vacating competitive seats backed the bill: Sens. Roy Blunt of Missouri, Richard Burr of North Carolina and Rob Portman of Ohio. As CNN's Manu Raju and Alex Rogers have reported, that puts them at odds with many of the Republicans vying to replace them, underscoring how today's GOP candidates are much more likely to follow Trump's lead than their senators'.

After Pennsylvania, Democrats' best pick-up opportunities remain Wisconsin and North Carolina, where one GOP senator -- Sen. Ron Johnson -- still hasn't made up his mind about running for reelection and the other, Burr, announced five years ago that this would be his last term. Democrats are attacking Johnson for voting against the infrastructure package and they're deploying a similar line against Sen. Marco Rubio in Florida. Republicans still have the advantage in the Sunshine State, but it's the eighth most likely to flip for the second month in a row.

Republicans' best pick-up opportunities are in Georgia and Arizona, two states that Biden and Senate Democrats flipped last cycle. Democratic Sens. Raphael Warnock, who won in a 2021 runoff, and Mark Kelly, who won last year, face reelection again next fall for full six-year terms.

Here are the 10 seats most likely to flip:

1. Pennsylvania

Incumbent: Republican Pat Toomey (retiring)

The Democratic field in this top pick-up opportunity got a new candidate last week, when Rep. Conor Lamb made official his campaign to replace Toomey. The Marine veteran and former prosecutor, whom Biden once said "reminds me of my son Beau," joins Lt. Gov. John Fetterman -- the biggest fundraiser in the race -- Montgomery County Commissioner Val Arkoosh, who has the backing of EMILY's List, and state Rep. Malcolm Kenyatta as the major candidates trying to flip this seat blue. Lamb first came to Congress in a 2018 special election, winning a conservative district that Trump had carried comfortably two years earlier. Like Fetterman, he's from the western part of the state, but unlike the former Braddock mayor, Lamb has tried to cut a more moderate image, which could be advantageous in a general election. Republicans haven't yet coalesced around a candidate of their own, but they're gleeful that a competitive Democratic primary may be pushing all their potential opponents to the left. Lamb, for example, has come out in support of ending the filibuster. Meanwhile, Republicans Jeff Bartos, a businessman, and Army veteran Sean Parnell, who lost a House race to Lamb in 2020, continue to duke it out, while Carla Sands, Trump's ambassador to Denmark and a top donor, announced her candidacy late last month. Former congressional candidate Kathy Barnette, who hadn't gotten much attention in the race so far, generated some buzz by outraising the other GOP contenders in the second quarter.

2. Georgia

Incumbent: Democrat Raphael Warnock

There's no question that Georgia, where Warnock is running for a full six-year term, will be a close race. But that's not quieting GOP anxiety over who their candidate will be. All eyes are still on Herschel Walker, who's received encouragement from Trump but lives in Texas and has yet to get in the race. Plenty of Republicans are hoping he doesn't get in, with a recent Associated Press report detailing his past -- including that he threatened violence against his ex-wife -- deepening concerns that he could jeopardize this top GOP pick-up opportunity. Senate Minority Leader Mitch McConnell has privately raised the idea that former Sens. Kelly Loeffler and David Perdue, both of whom lost in runoffs earlier this year, should reconsider this race, CNN reported last week. While the party establishment desperately searches for someone besides Walker, the idea that the Heisman Trophy winner already has Trump's blessing may make it more daunting for other would-be candidates to throw their hats in the primary ring. Three candidates are already running, including state Agriculture Commissioner Gary Black, who tried to attack Walker in a digital ad last week in which he rides a tractor and says he's "had Georgia plates all my life," a not-so-subtle dig at Walker's June video teasing a Senate run by revving the engine of a car with Peach State license plates. Biden only narrowly carried Georgia -- as did Warnock and Sen. Jon Ossoff -- so no matter who the Republican nominee is, Warnock is likely to have a fight on his hands. But for now, he has the race largely to himself, allowing him to start the third quarter with more than $10.5 million in the bank.

3. Wisconsin

Incumbent: Republican Ron Johnson

While everyone waits to see whether Johnson runs for a third term, Democratic Lt. Gov. Mandela Barnes is, quite literally, running -- announcing his campaign in a video late last month in which he laces up his sneakers at 6 a.m. and hits the streets. State Sen. Chris Larson soon ended his campaign and endorsed Barnes, leaving state Treasurer Sarah Godlewski and Milwaukee Bucks executive Alex Lasry as the other major Democratic candidates, although the race got another new candidate last week in Wisconsin Emergency Management Administrator Darrell Williams. Johnson raised $1.2 million in the second quarter -- more than double his first-quarter haul -- but he still hasn't said whether he's seeking a third term. As the only GOP incumbent who hasn't announced a retirement who's running for reelection in a Biden state, he would automatically be vulnerable. But some Democrats believe that his increasing penchant for peddling conspiracy theories -- about the 2020 election, the January 6 insurrection and the coronavirus and vaccines -- may make the race even more winnable for them than if this were an open seat.

4. Arizona

Incumbent: Democrat Mark Kelly

Kelly is running for a full six-year term after flipping this seat blue last fall. While Republicans fretted earlier this year that they lacked a candidate in one of their top pick-up opportunities, there's a bevy of candidates lining up to take on Kelly, while Gov. Doug Ducey -- one of Trump's favorite Republicans to attack -- insists he isn't running. Blake Masters, the president of the Thiel Foundation, launched his campaign last month, with expectations that Thiel will invest $10 million in a super PAC for him. He joins retired Maj. Gen. Michael "Mick" McGuire, the state's top National Guard officer who also headed Arizona's emergency response department during the pandemic, Attorney General Mark Brnovich and solar energy entrepreneur Jim Lamon in the race. But much of the early jockeying here isn't about the 2022 election -- it's about relitigating the last one, when Biden became just the second Democrat to win the state since 1948 and then-GOP Sen. Martha McSally lost. Masters told CNN in an interview when he announced that "it's really hard to know" who won the presidential race. Upping the pressure on local Republicans to embrace that perspective, Trump traveled to the Grand Canyon State later that month for a misleadingly called "Rally to Protect our Elections," seizing on Maricopa County's partisan audit and repeating his lies about election fraud.

While it's a powerful narrative among some Republicans -- including the state party, which earlier this year censured Ducey -- there's a risk that parroting too much Trump talk about stolen elections will turn off the same suburban voters who (twice) rejected McSally's efforts to cozy up to the former President. Republicans are hitting Kelly on the border, while some in Washington are showing plenty of love for the state's other Democratic senator, Kyrsten Sinema. North Carolina Sen. Thom Tillis, for example, recently published an op-ed praising her efforts on the bipartisan infrastructure bill, while the National Republican Senatorial Committee has been trying to use Sinema as a foil to argue that Kelly isn't as moderate as he says he is. As Republicans fight amongst themselves -- and will for another year, given the state's late primary -- Kelly ended the second quarter with nearly $7.6 million in the bank.

5. North Carolina

Incumbent: Republican Richard Burr (retiring)

This is one open race where Trump has already weighed in, throwing his weight behind GOP Rep. Ted Budd to replace retiring Sen. Richard Burr in a surprise endorsement earlier this summer. But it hasn't winnowed the field -- former Gov. Pat McCrory is still running, as is former Rep. Mark Walker. The political arm of the conservative Club for Growth, which has been with Budd since he emerged from a 17-way primary to come to Congress in 2016, recently ran an ad during the Olympics attacking McCrory, whose previous campaigns and time in statewide elected office make him a well-known commodity in the race. On the Democratic side, former state Supreme Court Chief Justice Cheri Beasley, who's running with the backing of EMILY's List, raised about $1.3 million during the second quarter, despite not being in the race for the full quarter -- more than either state Sen. Jeff Jackson or former state Sen. Erica Smith raised during that period. Democrats have struggled in North Carolina at the Senate and presidential levels recently, but there's excitement that running a non-White male candidate could drive turnout among minority voters, especially in some of the rural areas where Republicans have continued to hold an advantage. Higher Heights PAC, which works to elect progressive Black women, and the political arm of the Congressional Black Caucus both endorsed Beasley this summer.

6. New Hampshire

Incumbent: Democrat Maggie Hassan

Still waiting... that's the refrain in the Granite State, where Republicans (and Democrats) are watching to see when Gov. Chris Sununu will make a decision about challenging Hassan. Trump has said he would like to see him run -- as would establishment Republicans. He had said he'd make a decision after the end of the legislative session, but that deadline has come and gone. "I'm not going to make a decision for a while," Sununu said last week on the "Ruthless" podcast, hosted by longtime McConnell adviser Josh Holmes. While the holdup may be frustrating some Republicans, Sununu is probably right that he has time. As a sitting governor, he doesn't need to introduce himself to voters. (Hassan, herself a former two-term governor, didn't announce for Senate until October 2015.) And if he doesn't run, the GOP may have another good option in former Sen. Kelly Ayotte, who only lost to Hassan by 1,017 votes in 2016. Democrats, meanwhile, are trying to turn the GOP excitement for Sununu into an attack by tying him to McConnell, launching digital ads last week about how they are "two sides of the same coin." They're also leaning hard into Sununu's signing of a budget with abortion restrictions -- an issue that could be problematic for the Republican in a state that's increasingly trended blue in federal elections.

7. Nevada

Incumbent: Democrat Catherine Cortez Masto

Republicans are also waiting in Nevada, where there's not yet a major challenger to first-term Democratic Sen. Catherine Cortez Masto. But that could soon change. All eyes have been on former Attorney General Adam Laxalt, who's hosting his Basque Fry next weekend with a list of speakers that includes conservative heavyweights like Florida Gov. Ron DeSantis, Arkansas Sen. Tom Cotton and David McIntosh, the president of the Club for Growth. If Laxalt doesn't run for Senate, it's not clear the party has a backup in the same way the GOP does in the Granite State, especially with so many other Republicans in Nevada running for governor. Cortez Masto, the first Latina senator and the former chair of the Democratic Senatorial Campaign Committee, ended the second quarter with more than $6.5 million in the bank.

8. Florida

Incumbent: Republican Marco Rubio

This race moved up one spot on the list last month -- and Democratic Rep. Val Demings' quarterly fundraising report, released later in July, underscored why: she raised nearly $4.7 million, ending the period with about $3 million in the bank. Rubio raised about $4 million, but still had a hefty cash-on-hand advantage of more than $6 million. Republicans scoff at big Democratic fundraising, arguing that it's become standard in the Trump era and isn't necessarily indicative of victory. And while past races have shown that money certainly isn't everything, it can say something about the strength and enthusiasm around a certain candidate -- not to mention it's pretty useful for Florida's expensive media markets. Rubio still has the clear advantage in this state that Trump won by 3 points, but Democrats are enthused about their candidate and think Rubio's vote against infrastructure gives them a powerful attack.

9. Ohio

Incumbent: Republican Rob Portman (retiring)

Portman isn't running for reelection, although he's still a crucial player in the Senate, leading GOP negotiations over the bipartisan infrastructure bill. The crowded field of Republican candidates vying to replace him isn't on board with the compromise -- just one example of how Republican candidates in open-seat races are trying to run much closer to Trump than to the incumbent. Former state Treasurer Josh Mandel, former state party chair Jane Timken, businessmen Mike Gibbons and Bernie Moreno and "Hillbilly Elegy" author JD Vance are all hoping a Trump endorsement will come their way, but so far the ex-President has stayed out of the race. Vance has benefited from a surge of earned media since his announcement last month, and he already had the backing of a super PAC with a $10 million cash infusion from Thiel. But his high profile has also led to scrutiny of his past anti-Trump comments, including calling him a "moral disaster," as CNN's KFile has reported. Democrats are ready to use Republicans' opposition to the infrastructure plan against them, and Rep. Tim Ryan -- who raised more $3 million in the second quarter -- is consolidating support with the backing of Rep. Joyce Beatty, the chair of the Congressional Black Caucus. But in a state Trump won by 8 points, Ryan still faces an uphill battle to replicate Sen. Sherrod Brown's success of winning statewide here.

10. Missouri

Incumbent: Republican Roy Blunt (retiring)

The fallout from Blunt's decision not to run for another term jolted a race that should never have been competitive onto the list of seats most likely to flip. Other Republican retirements in red states have undoubtedly made races more competitive -- see Ohio above, for example -- but Blunt's impending departure has created an opening for former Gov. Eric Greitens, who resigned from office following a probe into allegations of sexual and campaign misconduct. Republicans haven't forgotten 2012, when Todd Akin's "legitimate rape" comments cost them a Senate race here. And the problem for Missouri Republicans this year is that more of them keep launching campaigns, which could eventually splinter the anti-Greitens vote and reduce the threshold he needs to win the primary. GOP Rep. Billy Long recently announced his campaign, joining Rep. Vicky Hartzler, Attorney General Eric Schmitt and Mark McCloskey, whom the Republican governor recently pardoned after he and his wife had pleaded guilty to misdemeanor charges for pointing guns at protesters near their home last summer. The only other GOP woman in the congressional delegation, Rep. Ann Wagner, announced she'd run for reelection instead. On the Democratic side, former Gov. Jay Nixon also announced he'd pass, putting an end to the chatter that the bigger-name would jump in now that Greitens' candidacy is making a solid Republican seat, in a state carried by 15 points, look more vulnerable. Democrats have a handful of lesser-known candidates, and some who are still eying the race, who could still make this race competitive -- or at least force the national GOP to spend money defending the seat.

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