RALEIGH, N.C. (AP) — North Carolina voters are choosing between a Republican U.S. senator and Donald Trump ally who has been criticized for voting to repeal the Affordable Care Act, and a Democratic challenger who admitted in the campaign's final weeks to sending sexually suggestive texts to a woman not his wife.

Tuesday's contest between Sen. Thom Tillis and Cal Cunningham is the most expensive Senate race in U.S. history. More than $280 million has been spent by the campaigns and by outside groups, according to the Center for Responsive Politics. National Democrats have invested significantly in the presidential battleground state, hoping to make the seat one of the handful that need to flip to take back the Senate.

The state has already seen record early voting by mail and in person, with nearly 4.6 million ballots, or 62% of all registered voters, cast as of Monday afternoon, according to the State Board of Elections.

Focused for months on COVID-19, health insurance and taxes, the race pivoted four weeks ago when Cunningham, 47, acknowledged that he had written the sexually suggestive texts to a public relations strategist from California. He apologized, saying he was “deeply sorry.” A few days later, The Associated Press reported additional texts and interviews confirming he and the woman had an intimate encounter as recent as July.

The revelations gave life to Tillis’ campaign, which used interviews with the senator and political ads to question Cunningham's integrity. Before the revelation, Cunningham, a U.S. Army reserve officer and Iraq War veteran, had presented himself as a family man and dogged military prosecutor.

After the revelation, Cunningham stuck to a low-profile schedule, holding small, unannounced events that were revealed after the fact on social media. In the sole online news conference he held, he refused to say whether he had had other affairs.

Cunningham, 47, a former state legislator and 2010 Senate candidate, had been recruited to run for the seat by national Democrats including Senate Minority Leader Chuck Schumer. Cunningham outraised Tillis dramatically this year, but Tillis, a former state House speaker, benefited from independent expenditure groups.

Still, it was Cunningham and allied groups who flexed their financial muscles in the final weeks. They flooded the airwaves with commercials focusing on Tillis’ votes to repeal President Barack Obama’s 2010 health care law and a state legislative career that included blocking Medicaid expansion.

Registered Democrat Ronald Minter, 52, an apartment maintenance worker from Raleigh, said Cunningham's personal issues weighed on him. But Minter said he still voted for Cunningham.

“No man is perfect, but every man deserves a second chance,” Minter said. “He thinks that he can redeem himself."

Tillis, 60, a former IBM consultant, last year frustrated some conservatives who accused him of failing to embrace Trump fully. But Republican Fred Schroeder of Chocowinity said he was pleased with the senator and that he needs to win to keep the GOP in control of the chamber.

“Tillis is doing his job,” said Schroeder, 81, who is retired from the steel industry. “I don’t think he’s done anything bad ... and he hasn't embarrassed anyone that I know of.”

Cunningham’s acknowledgement of his extramarital activity on Oct. 2 came a couple hours after Tillis announced he tested positive for the coronavirus. Several days earlier, the senator had attended the White House event announcing the nomination of Amy Coney Barrett to the Supreme Court. A strong proponent of constituents wearing facemasks, Tillis acknowledged making a mistake by taking off his mask while indoors at the event.

Libertarian and constitution party candidates also are running for the seat.

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