HARRISBURG, Pennsylvania — President Trump faced the strongest test yet of his ability to shape a new generation of Republicans on Tuesday night, as voters rallied around one of his hand-picked choices for a critical U.S. Senate seat and were considering another.In North Carolina, Mr. Trump picked up an easy victory with Representative Theodore Budd winning the Republican Senate primary. Mr. Trump elevated the little-known congressman using a surprise endorsement nearly a year ago.Mr. Budd will face a Democratic former state supreme court justice, Cheri Beasley, who is aiming to become North Carolina’s first black senator.But much of the attention centers on Pennsylvania, where the Democratic lieutenant governor, John Fetterman, easily secured his party’s nomination for an open Senate seat, despite being forced off the campaign trail by a stroke. The 52-year-old cast an emergency absentee ballot from the hospital and later tweeted that he’d successfully undergone surgery to install a pacemaker and was “on track for a full recovery.”One of the biggest questions of the night is who will compete against Mr. Fetterman in the fall. Mr. Trump’s preferred candidate, Mehmet Oz, has divided conservatives and faces what looks like a far tougher race. Some are suspicious of the ideological leanings of the celebrity heart surgeon who gained fame as a frequent guest on Oprah Winfrey’s talk show. Dr. Oz has spent much of the campaign in a heated fight with a former hedge fund CEO, David McCormick.That’s allowed commentator Kathy Barnette to emerge in the final days of the primary as a conservative alternative to both Dr. Oz and Mr. McCormick. Should she win the primary and general election, Ms. Barnette would be the first black Republican woman elected to the U.S. Senate.Mr. Trump, who has held campaign-style rallies with Dr. Oz, insists he is the best candidate to keep the Senate seat in Republican hands in the fall. Given his level of involvement in the race, a loss would be a notable setback for the former president, who is wielding endorsements as a way to prove his dominance over the GOP ahead of a potential 2024 presidential run.The year’s midterm primary season is entering its busiest stretch with races also unfolding in Kentucky, Oregon, and Idaho.Meanwhile, the Pennsylvania attorney general, Joshua Shapiro, who was unopposed for the Democratic party’s gubernatorial nomination, tweeted that he had mild Covid-19 symptoms that were forcing him from the campaign trail.Tuesday’s contests could ultimately determine how competitive the general election will be this fall, when control of Congress, governor’s mansions, and key elections posts are up for grabs. That’s especially true in the perennial political battleground of Pennsylvania, where some Republicans are already worried that state Senator Douglas Mastriano is too extreme to woo moderates who are often decisive in general elections.“There’s definitely some concern in large factions of the party,” said a Pennsylvania Republican strategist, Vince Galko.More fundamentally, Tuesday’s primaries could test voters’ commitment to democratic principles. Ms. Barnette is running even further to the right than Dr. Oz and participated in the January 2021 rally that turned into a riot at the Capitol.Then there’s Mr. Mastriano, who was also outside the Capitol during the mob attack and would appoint Pennsylvania’s chief elections official if he becomes governor. He has pledged to take the extraordinary step of requiring voters to “re-register” to vote — even though that’s barred by the National Voter Registration Act and likely violates significant protections under federal, and possibly state, law.Mr. Mastriano made Mr. Trump’s claims about widespread electoral fraud costing him the presidency a centerpiece of his campaign — and has been subpoenaed by the House committee investigating the Capitol riot following his efforts to name a slate of alternate Electoral College electors in Mr. Trump’s favor.Stacy Steinly, a 51-year-old school bus assistant, cast her ballot in the town of Hamburg, Pennsylvania, about 30 miles west of Allentown. She said she chose Mr. Mastriano because “he was sticking by President Trump and saying that everything was fraudulent.”“Everything he was talking about was making sense,” said Ms. Steinly, who wore a black T-shirt that said “Biden is not my president (or anyone else’s) based on legal votes.”Mr. Trump’s safest bet might have been Mr. Budd, who overcome a slow start to emerge from 14 Republican primary candidates, including former Governor Patrick McCrory, as the winner of North Carolina’s Republican Senate primary.While much of the attention during the opening phase of the primary season has focused on Mr. Trump’s grip on the GOP, the contests also serve as a referendum on President Biden’s leadership of the Democratic Party. In the president’s native state of Pennsylvania, Representative Conor Lamb, a moderate in Mr. Biden’s mold, was handily beaten by Mr. Fetterman.Mr. Lamb said Tuesday he had detected “frustration” among Democratic primary voters, a feeling he said he shared as the party has struggled to accomplish much of its policy agenda. Yet he argued that moderates helped Democrats retake control of the House in 2018 and that the party should “double down” on that approach this year.“What I’ve been trying to do throughout this campaign is talk about the fact that no matter how difficult it is, we actually know as a party what it takes to be successful,” Mr. Lamb told a Pittsburgh radio station.Mr. Fetterman, known for his hulking, 6-foot-8 stature and tattoos, and for championing causes such as universal health care, has appealed to many Democrats with an outsider image.Robert Sweeney, 59, also from Hamburg, said he voted for Mr. Fetterman because “he seemed like a decent guy and knows what he’s doing.”
