Sen. Lindsey Graham was the projected winner Tuesday night in South Carolina’s closely watched U.S. Senate race, fending off his Democratic opponent Jaime Harrison with just 36% of the votes counted.

WHO IS LINDSEY GRAHAM? 5 THINGS TO KNOW ABOUT THE SC SENATOR

Graham and Harrison were locked in a dead heat for much of the election cycle, but despite record-breaking fundraising hauls by his opponent, Graham managed to secure the seat Republicans have held for nearly two decades. 

In three previous races -- in 2002, 2008 and 2014 -- Graham sailed to victory by double digits, and on Tuesday, even with partial results reported, he was ahead of Harrison 55% to 43%.

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Despite that, Graham faced bitter criticism, even among supporters in his own party, who slammed his shifting policies and loyalty to President Trump.

On top of that, Harrison stunned with a massive cash haul, raking in $107.6 million -- the highest of any Senate candidate in U.S. history -- while Graham raised $72.7 million.

WHO IS JAIME HARRISON? 5 THINGS TO KNOW ABOUT THE SOUTH CAROLINA SENATE CANDIDATE

But money alone wasn’t enough for Democrats to take the seat.

Graham’s win buoyed Republicans fighting to maintain control of the upper chamber, which they’ve dominated since 2014.

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Democrats need a net gain of three seats in the Senate, and the White House, to win back the majority -- or four seats if President Trump is reelected. Republicans have held a 53-47 majority since 2018. 

The races in which Democrats have their best pick-up opportunities were against Sens. Cory Gardner in Colorado, Martha McSally in Arizona, Thom Tillis in North Carolina and Susan Collins in Maine.