Senate Minority Whip John Thune (R-S.D.) on Monday endorsed Herschel Walker’s bid to oust Sen. Raphael Warnock (D-Ga.) in the latest sign that GOP leaders are warming up to the former football star’s Georgia Senate campaign.

“I am proud to endorse Herschel Walker for U.S. Senate in Georgia,” said Thune, the No. 2 Senate Republican leader. “Herschel Walker is a fighter, a uniter, and a proven winner with the ability to bring Republicans together to win in November.”

Thune is the fifth Republican senator to throw his support behind Walker and the first member of Senate GOP leadership to do so. Republican Sens. Josh Hawley (Mo.), Steve Daines (Mont.), Roger Marshall (Kan.) and Lindsey Graham (S.C.) have already endorsed Walker in the race to unseat Warnock.

Walker announced his campaign in August after months of encouragement from former President Trump. 

Republican leaders in Washington were at first wary of the former NFL star’s Senate bid, given his lack of political experience and revelations of a turbulent past. But those concerns have largely subsided, and party leaders now see Walker as their best bet to defeat Warnock next year.

The Georgia Senate race is among the most closely watched contests of the 2022 midterm cycle. Warnock flipped the seat previously held by former Sen. Kelly Loeffler (R-Ga.) in a runoff election earlier this year, just two months after President Biden became the first Democratic presidential candidate in nearly 30 years to win the state.

Warnock’s victory, along with that of Sen. Jon Ossoff (D-Ga.) in a separate runoff election, helped hand Democrats control of the Senate. But the 2022 Georgia Senate race is a key offensive opportunity for Republicans, who are hoping to recapture the Senate majority next year.