By Jarrett Renshaw and Joseph Ax
PHILADELPHIA (Reuters) - Voters in Pennsylvania and North Carolina will pick nominees in critical U.S. Senate and gubernatorial contests on Tuesday that provide another test of former President Donald Trump's sway with Republican voters ahead of November's midterm elections.
Idaho's incumbent Republican governor also faces a Trump-backed primary rival, while Trump ally Madison Cawthorn, a first-term Republican congressman who has generated numerous controversies, hopes to fend off a primary challenge in North Carolina.
President Joe Biden's fellow Democrats are fighting to retain their slim majorities in the House of Representatives and Senate in the Nov. 8 congressional elections. Democrats in Pennsylvania and North Carolina are trying to win Senate seats currently held by Republicans.
The Pennsylvania Republican senatorial primary has turned into an unpredictable three-way battle in its final days after conservative political commentator Kathy Barnette surged into contention against two better-funded rivals: Trump-endorsed TV wellness celebrity Mehmet Oz and former hedge fund chief executive David McCormick.
In the Democratic primary, progressive Lieutenant Governor John Fetterman, who is finishing his primary campaign from a hospital after suffering a stroke last week, faces centrist U.S. Representative Conor Lamb.
Barnette's rise has worried some establishment Republicans concerned that the right-wing activist could prove too conservative for general election voters choosing a successor to retiring Senator Pat Toomey.
In North Carolina, Trump-endorsed congressman Ted Budd leads former Governor Pat McCrory in polls as they vie to succeed retiring Senator Richard Burr. Cheri Beasley, the first Black woman to serve as chief justice of North Carolina's Supreme Court, is expected to win the Democratic nomination.
Trump has endorsed more than 150 candidates as he tries to solidify his status as his party's kingmaker, though his picks have not always prevailed. His support helped author J.D. Vance win the Ohio Senate primary, but his favored candidate lost in Nebraska's gubernatorial race last week.
Republicans are well positioned to regain control of the House, which could enable them to frustrate Biden's legislative agenda. Democrats have a better chance of keeping control of the Senate, currently split 50-50 between the parties with Vice President Kamala Harris holding the tie-breaking vote.
The 6-foot-8-inch (2.03 m) tattooed and goateed Fetterman, who has a penchant for hoodies and liberal stances, has proven to be an adept fundraiser and a social media force.
His health scare has added a new wrinkle to the Pennsylvania race. Fetterman canceled his planned appearance at a Pittsburgh election night party after revealing on Sunday he had suffered a stroke two days earlier precipitated by a blood clot. He said he was recovering and has not sustained cognitive damage.
Polls show Fetterman leading Lamb, whose moderate politics make him a better general election candidate in the view of many party insiders.
Barnette, seeking to become the state's first Black U.S. senator, has called her rivals insufficiently conservative, but has her own baggage. She was photographed, according to news reports, marching toward the U.S. Capitol on Jan. 6, 2021, alongside members of the far-right Proud Boys group shortly before a mob of Trump supporters attacked police and stormed the building in a failed bid to overturn his 2020 election loss.
Barnette's campaign in a statement to NBC said she did not take part in or condone the destruction of property and has no connection to the Proud Boys. She also has defended herself over several Islamophobic messages she posted years ago.
Trump last week endorsed state Senator Doug Mastriano, who is leading the polls in Pennsylvania's Republican gubernatorial primary. Mastriano also was present outside the Capitol on the day of the riot after Trump delivered a speech to followers repeating his false claims that the election was stolen from him through widespread voting fraud.
Some Pennsylvania Republicans view Mastriano, like Barnette, as too extreme to win a general election.
Abortion has become a flashpoint issue in the race since a leaked draft opinion showed the Supreme Court's conservative bloc is poised to overturn Roe v. Wade, the 1973 decision legalizing abortion nationwide. Mastriano said he would pursue a statewide abortion ban. State Attorney General Josh Shapiro, the Democratic front-runner, vowed to protect abortion rights.
Cawthorn, at 26 the House's youngest member, faces a challenge from Republican state Senator Chuck Edwards. Cawthorn has turned some in his own party against him with a string of embarrassing episodes, including a claim that legislative leaders invited him to a cocaine-fueled orgy, two attempts to bring a gun onto a plane and a old video that appeared to show a naked Cawthorn gyrating against someone.
In Idaho, incumbent Republican Governor Brad Little faces Trump-backed primary challenger Janice McGeachin, the state's lieutenant governor.
Primary elections also take place in Kentucky and Oregon.
(Reporting by Jarrett Renshaw in Philadelphia and Joseph Ax in New York; Editing by Will Dunham and Scott Malone)