Sen. Susan Collins has won a tough re-election fight against a well-funded Democratic opponent, according to the Associated Press.

Collins’ Democratic challenger Sara Gideon, the Speaker of the Maine House of Representatives, conceded the race on Wednesday in front of a crowd of supporters. In the lead-up to Election Day, Gideon was the favorite to win the race, with FiveThirtyEight estimating that she would claim victory.

Significantly, Collins was the sole GOP Senator up for re-election who did not receive an endorsement from President Donald Trump. Generally agreed to be the most moderate GOP Senator, she has made a name for herself for breaking with the rest of her caucus and the president more often than her colleagues. This has put her on the receiving end of criticism from more conservative Republicans.

Despite being somewhat of a centrist, Democrats don’t like her either. After deciding to vote with the rest of the Senate Republicans in controversially confirming Brett Kavanaugh to the Supreme Court in 2018, Democrats all across the country started to raise millions of dollars in funds to unseat Collins in 2020, making this campaign the toughest that she ever faced.

Collins squeaked past Gideon and the other two candidates on the ballot, managing to win just over a majority of votes. This was the first election in which Maine used its recently adopted ranked-choice voting system to vote for candidates for president and the U.S. Senate. Because Collins was able to get over 50% of people’s first-choice votes, no instant runoffs occurred.

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