(Bloomberg) -- Former President Donald Trump endorsed Republican Representative Mo Brooks in the 2022 GOP primary to replace retiring Alabama Senator Richard Shelby, choosing a leader in the fight to overturn his Nov. 3 election loss over one of his former ambassadors.

Both Brooks and Lynda Blanchard, Trump’s ambassador to Slovenia, had been vying for Trump’s endorsement in the Republican primary race. Trump spoke at a fundraiser Blanchard held for her campaign at the former president’s Mar-a-Lago resort last month.

Brooks helped lead the Jan. 6 challenge of Electoral College votes cast for President Joe Biden and was a prominent speaker at a rally in Washington before Trump’s supporters stormed the U.S. Capitol, and Trump cited Brooks’s willingness to fight for his “America First” agenda.

“Mo is a great conservative Republican leader, who will stand up for America First no matter what obstacles the fake news media, RINOs, or socialist Democrats may place in his path,” Trump said in the endorsement released through his political action committee, referring to “Republicans In Name Only.”

Shelby, 86, a six-term senator, announced in February he would retire from the Senate when his term ends, creating an open seat in the 2022 election. It’s one of five Republican Senate seats coming open next year.

Endorsements typically don’t matter much, but Trump still has strong support among Republican voters -- especially in Alabama, which he carried handily twice -- and the former president is promoting the idea of his endorsement being the ticket to election. Trump is vowing to support candidates loyal to him and his agenda as the GOP aims to retake control of Congress in the 2022 midterm elections.

Brooks, 66, was also endorsed last month by former White House adviser Stephen Miller, an architect of the Trump administration’s hard-line immigration policy and a former aide to onetime Alabama Senator Jeff Sessions.

Blanchard, 61, who introduced herself in a video announcing her candidacy as “a proud member” of the Make America Great Again movement who’s grateful for Trump’s leadership, said in a statement she remains committed to the race and to Trump.

“I intend to go to Washington as the United States Senator from Alabama to represent the America First agenda that President Trump championed every day,” she said.

Other Republican candidates considering the race include Alabama Secretary of State John Merrill and Katie Boyd Britt, president and chief executive of the Business Council of Alabama and Shelby’s former chief of staff.

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