Pennsylvania U.S. Senate candidate Dr. Mehmet Oz speaks during a Republican leadership forum at Newtown Athletic Club on May 11, 2022 in Newtown, Pennsylvania.Michael M. Santiago | Getty ImagesTwo of former President Donald Trump’s highest-profile endorsements hope to emerge victorious from no-holds-barred Republican primary races in Pennsylvania and North Carolina as the pivotal midterm election season heats up.Voters in those states, along with Kentucky, Idaho and Oregon, will head to the polls Tuesday in the biggest day of the primary election cycle to date.It may also be the most dramatic. One of Trump’s preferred candidates, Rep. Madison Cawthorn, of North Carolina, is fighting to stay above water as a torrent of scandals, missteps and vicious attacks — including harsh criticism from his fellow Republicans — threaten to sink his reelection bid.In Pennsylvania, Trump has backed Dr. Mehmet Oz, the former host of “The Dr. Oz Show,” who is one of three top contenders in an intense — and intensely expensive — battle for an open Senate seat.Rep. Madison Cawthorn (NC-11) makes remarks at the Hilton Anatole Hotel in Dallas, Texas on Friday, July 9, 2021.Emil Lippe | The Washington Post | Getty ImagesThe races could give a read on the political influence wielded by Trump, who has endorsed more than a dozen candidates competing in Tuesday’s contests. Most of the former president’s picks have so far won their primaries, with the exception of Nebraska gubernatorial candidate Charles Herbster. He lost his primary race last week after multiple women accused him of sexual misconduct. Herbster denied those allegations.The Republican Party is hoping to win control of the House and Senate in the midterms this fall, while Trump, who has strongly hinted he is considering another run for president in 2024, is hoping to cement his status as the de facto leader of the GOP. The outcome of Tuesday’s primaries could impact both prospects.Here’s what to watch:North CarolinaThe Tar Heel State’s 11th Congressional District is currently considered a safely Republican seat no matter who wins Tuesday. But the GOP primary has nevertheless become a must-watch race, thanks to Cawthorn’s penchant for seizing attention — and courting controversy.Cawthorn in 2020 won the seat that Republican former Rep. Mark Meadows had vacated in order to take a job as Trump’s White House chief of staff. The youngest member of Congress, at 26 years old, Cawthorn quickly gained buzz, receiving an endorsement from Trump less than three months after being sworn in to office.That blend of name recognition, incumbency and an endorsement from Trump might have made Cawthorn a shoo-in in his solid-red district. But his actions and remarks in recent months have made him a target on both sides of the aisle.In a March podcast interview, he accused lawmakers of doing drugs and claimed that unidentified members of Congress invited him to orgies. The comments prompted outrage from Republicans in Washington, including House Minority Leader Kevin McCarthy.That same month, Cawthorn was reportedly charged with driving with a revoked license, while also facing two citations for speeding.In April, Cawthorn was cited on a misdemeanor criminal charge for bringing a handgun to a North Carolina airport. It was the second known time he had done so.Later that month, ethics watchdogs raised suspicions about possible insider trading by Cawthorn over his relationship to an anti-Biden cryptocurrency. Sen. Thom Tillis, a fellow North Carolina Republican, called for a House ethics probe into the allegations.Tillis had already endorsed State Sen. Chuck Edwards for Cawthorn’s seat. Edwards, one of seven Republicans challenging Cawthorn, is now considered to be a top contender in the primary.Earlier in May, a political action committee calling itself Fire Madison Cawthorn released a video showing the congressman naked in a bed and thrusting on top of another person. Cawthorn said the video was from “years ago” and that he was “being crass with a friend.”Those and other behaviors appear to have taken a toll, according to recent polling, but Cawthorn may still hold an insurmountable lead.Trump reiterated his support for Cawthorn on Sunday night, writing in a social media post that “when Madison was first elected to Congress, he did a great job.” Trump noted that Cawthorn had gone through a “traumatic experience” at age 18, when he was in a car crash that has required him to use a wheelchair ever since.”Recently, he made some foolish mistakes, which I don’t believe he’ll make again … let’s give Madison a second chance!” Trump wrote.Polls in the North Carolina primary are open from 6:30 a.m. ET to 7:30 p.m. ET. PennsylvaniaPennsylvania was one of the most competitive swing states in the 2020 presidential election, and it is shaping up to be a major battleground in the fight for the Senate majority.Money has poured into the state’s Senate Republican primary: Candidates and political groups have spent more than $55 million on television and radio ads alone, according to ad tracker Medium Buying.After much jostling for position, polls now show an extremely tight race between Oz, ex-hedge fund CEO Dave McCormick and right-wing commentator Kathy Barnette, who has experienced an eleventh-hour surge in support.The three top candidates are fighting to compete in the general election for the Senate seat being vacated by retiring Republican Sen. Pat Toomey.The purple-state Senate seat is far from a lock for the GOP: The state’s other senator is Bob Casey, a Democrat, and Toomey narrowly beat out Democrat Katie McGinty in the 2016 general election. The race could be one of the best chances Democrats have to flip a red seat blue and possibly keep control of the Senate past the midterms.Oz, a celebrity doctor who lived in New Jersey for two decades and has never held office before, has run into some speed bumps in Pennsylvania, despite Trump’s backing. He was reportedly booed during a campaign rally with Trump earlier this month. And he is nearly tied in the polls with Barnette, whose campaign has reportedly raised less than $2 million in total.Barnette’s rapid rise has been accompanied by a greater focus on her past anti-Muslim tweets, as well as reports that she was photographed marching toward the U.S. Capitol building on Jan. 6, 2021, the day that a violent mob of Trump’s supporters stormed the building.Whoever wins could face off against John Fetterman, the lieutenant governor of Pennsylvania who is the heavy frontrunner in the Democratic primary, according to numerous polls of the race.But two days before the primary, Fetterman, 52, announced that he had had a stroke.It was caused “by a clot from my heart being in an A-fib rhythm for too long,” Fetterman said in a statement. He said his wife, Gisele, took quick action to get him to a hospital, where doctors “were able to quickly and completely remove the clot, reversing the stroke.””The good news is I’m feeling much better, and the doctors tell me I didn’t suffer any cognitive damage. I’m well on my way to a full recovery,” Fetterman said. The illness will keep him from attending his election-night watch party in person, his campaign said Monday.Polls in Pennsylvania will be open from 7 a.m. ET to 8 p.m. ET on Election Day.