Cal Cunningham Concedes to Republican Sen. Thom Tillis in N.C. After Sex Scandal

Getty Images; Grayson barnette/wikipedia Thom Tillis and Cal Cunningham

After the most expensive — and one of the more controversial — Senate races in U.S. history, Sen. Thom Tillis has retained his North Carolina seat against challenger Cal Cunningham.

"I just called Senator Tillis to congratulate him on winning re-election to a second term in the U.S. Senate and wished him and his family the best in their continued service in the months and years ahead," Cunningham said in a statement Tuesday. "The voters have spoken and I respect their decision."

The race has been one the most closely watched campaigns in the 2020 election. The North Carolina contest was one of the flips the Democratic Party aimed for, in hopes of taking control of the Senate.

But Cunningham's bid was overshadowed in the final weeks by a sex scandal and his election hopes never materialized, as he received more than 2.5 million votes but lost to Tillis by about 93,000.

Now, all eyes have turned to Georgia, where two Senate run-off elections in January will determine the congressional body's majority.

Gerry Broome/AP/Shutterstock Cal Cunningham

Stefani Reynolds/AP/Shutterstock Sen. Thom Tillis

The road has been a long one for both Cunningham, 47, and Tillis, 60. The incumbent Republican senator had to quarantine after he was diagnosed with COVID-19 in early October.

That same week, the Associated Press reported Cunningham's intimate texts with a woman who was not his wife were leaked to a right-wing website.

“I have hurt my family, disappointed my friends, and am deeply sorry. The first step in repairing those relationships is taking complete responsibility, which I do,” Cunningham said in a statement.

At that point, the race had erupted into "chaos," one local political science professor told the AP.

“It’s chaos — it’s really what I see it is,” David McLennan, the Meredith College professor, said.

In the days leading up to the election, Cunningham was regularly ahead of Tillis in the polls. It helped that former Vice President Joe Biden was leading a tight race in the state against President Donald Trump, according to The Hill.

Cunningham, a lieutenant colonel in the Army Reserve, focused his race on ousting the second-term Republican and issues like health care.

Grayson barnette/wikipedia Cal Cunningham

State Democratic Party Chair Wayne Goodwin continued to voice his support for Cunningham after his scandal broke and lambasted Tillis.

"The fact is that there’s only one candidate who has blocked Medicaid expansion, voted to end protections for people with preexisting conditions, and enabled this administration’s bungled response to this pandemic, which is why North Carolina will send Cal to the U.S. Senate next month," he said in a press release, according to the AP.

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After the scandal broke, Cunningham kept his head low. Meanwhile, his opponent used the affair to attack Cunningham's integrity.

"He made truth and honor the foundation of his campaign and spent tens of millions of dollars talking about his military service, talking about his family, talking about truth and honor," Tillis said in an interview, according to Politico. "It’s not about the substance of the affair. It’s about the theme that he used as a basis for trying to convince the people of North Carolina that he was a truthful and honorable person."

Erin Schaff/Getty Images Thom Tillis

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Joe Biden unanimously won the race in the township of Dixville Notch, while voters in Millsfield backed incumbent Donald Trump

Beyond questioning Cunningham's moral values, Tillis also tied his candidacy closely to the president's. He attended Trump events — he tested positive for COVID-19 days after attending the Supreme Court nomination ceremony for Amy Coney Barrett in the Rose Garden, which has since been labeled a "super-spreader event" — and assured voters at his own campaign rallies that he would work hard for them, if he maintained his seat in the Senate.

"I’m going to do everything I can, I won’t leave anything on the table," Tillis told voters ahead of the election, The Hill reported.

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"I have to work hard because keeping up with the president is hard enough," he said. "I got to work at least as hard as him and I will, all through the election and for as long as I’m a U.S. senator."

Many argued that Republicans were hypocritical for denouncing Cunningham when Trump has been accused of affairs and sexual misconduct. (The president has denied all of the allegations.)

"I’ve certainly heard from a number of people who said if Republicans will vote for Trump then we can’t risk the election over these stupid text messages," Graig Meyer, a Democratic state representative from North Carolina, told the Intelligencer.