US President Donald Trump’s pick for Alabama’s Senate race has lost the state’s Republican primary to a firebrand Christian conservative.

Former Alabama Supreme Court Justice Roy Moore defeated Senator Luther Strange in the state’s Republican Senate primary runoff election on Tuesday, delivering a blow to Trump and Senate Majority Leader Mitch McConnell, who backed the incumbent legislator, ABC News reported.

Strange, 64, said he had called Moore to concede the race. “We wish him the best as he goes forward,” he told supporters. Moore advances to face Democratic nominee and former US Attorney Doug Jones in the general election contest on December 12.

The President made a personal investment in the Strange campaign, holding a rally for the senator — who was appointed in February to the seat formerly held by Attorney General Jeff Sessions — last week in Huntsville, where he admitted he “might have made a mistake” in backing the incumbent senator and pledged to back Moore should he win.

Vice-President Mike Pence also appeared with Strange at rallies. He also had the backing of Senate Majority Leader Mitch McConnell, and the Senate Leadership Fund pumped $7 million into the race.

In the past week, Trump and Pence travelled to Alabama to stump with Strange. “It was great being with Luther Strange last night in Alabama. What great people, what a crowd! Vote Luther on Tuesday,” the President had tweeted earlier.

But within minutes of the result, he had thrown his weight behind the winning Republican candidate.

“Congratulations to Roy Moore on his Republican Primary win in Alabama. Luther Strange started way back & ran a good race. Roy, WIN in Dec!”

Moore, 70, is best known for losing his position as the state’s top judge twice. The first time, he had flouted a court order to remove a Ten Commandments monument from the courthouse. In 2016, he ordered state probate judges not to issue same sex-marriage licenses, in defiance of the US Supreme Court’s ruling.

Moore, a bible-quoting evangelical, drew support from Christian conservative Sarah Palin and recently-sacked White House chief strategist Steve Bannon.