Sen. Thom Tillis (R) has won re-election against Democratic challenger Cal Cunningham in North Carolina, AP projects.Why it matters: Tillis' victory is a major win for Republicans as they fight to keep control of the U.S. Senate.Tillis was first elected in 2014 and has branded himself as a loyal defender of President Trump.Between the lines: Polls generally favored Cunningham, but both candidates were plagued by controversies in the run-up to the election. Cunningham's polling lead took a hit in early October after he admitted to having an extramarital affair.Tillis, meanwhile, faced criticism when he and several others tested positive for the coronavirus after attending a Rose Garden ceremony introducing Supreme Court nominee Amy Coney Barrett. Data: AP; Chart: Naema Ahmed, Andrew Witherspoon, Danielle Alberti/AxiosWhat they're saying: "While the results of this election suggest there remain deep political divisions in our state and nation, the more complete story of our country lies in what unites us: our faith and sense of confidence in our democracy, our civic values and common humanity, our shared aspiration to care for one another, and our belief that we live in a country that does exceptional things," Cunningham said in a statement conceding to Tillis.