Sen. Raphael Warnock (D-GA) won reelection Tuesday, fending off a spirited challenge from Republican Herschel Walker while helping Democrats grow their thin Senate majority in the midterm elections after a bruising four-week runoff campaign.

Warnock was leading Walker 50.4% to 49.6% when the race was called, earning the senator his first full six-year term after ousting an appointed Republican incumbent in a special election runoff nearly two years ago. Walker’s defeat was a major blow to the Republicans. They capped a disappointing midterm election season with yet another loss that effectively surrendered a Senate seat to the Democrats, who saw their majority grow from 50 to 51.

Republicans entered the Nov. 8 midterm elections expecting to ride a red wave to a pickup of at least one, but possibly five, Senate seats. But one by one, GOP opportunities dropped off the board.

Democratic incumbents presumed vulnerable won reelection in Arizona, Colorado, Nevada, New Hampshire, and Washington state, ensuring their party would at least retain its 50-seat majority, reliant on Vice President Kamala Harris’s tiebreaking vote, no matter what happened in Georgia. But after Sen.-elect John Fetterman (D-PA) flipped the seat being relinquished by retiring Sen. Pat Toomey (R-PA), Warnock became the Democrat’s path to an outright majority of 51.