WASHINGTON — Sen. Steve Daines, who leads the National Republican Senatorial Committee, endorsed Donald Trump for president on Monday.

The endorsement by Daines, R-Mont, is the former president’s first from a member of Senate GOP leadership in his 2024 bid.

In an appearance on Donald Trump Jr.’s “Triggered” podcast, Daines said he was “proud” to endorse Trump.

“The best four years I’ve had in the U.S. Senate is when President Trump was serving in the Oval Office,” Daines said, touting legislation that he said yielded “one of the greatest tax cuts in American history.”

“Joe Biden has empowered and emboldened our adversaries by his weakness. He just shivers under his desk during the day,” Daines added. “For these reasons and many others, I’m proud to endorse Donald J. Trump for president of the United States.”

NBC News reported on Thursday that Biden is preparing to formally announce his bid for a second term as soon as Tuesday, according to three sources familiar with his plans.

Daines also praised Trump’s stance on immigration, an issue the former president has highlighted in his campaign.

“Let’s finish building the wall, and let’s finish securing our southern border to protect our communities,” Daines said.

MAGA Inc., a super PAC aligned with Trump, highlighted Daines’ endorsement in an email Monday night.

As of Friday, Trump had won the support of more than 50 members of Congress, including nine senators and 48 representatives. More than half of the Florida Republicans serving in the House have given their endorsement, compared to just one for Florida Gov. Ron DeSantis, who has yet to declare his candidacy and is trailing Trump in the primary, according to a recent NBC News poll.

Daines’ endorsement for Trump comes as the field of GOP candidates continues to expand, with Nikki Haley, the former South Carolina governor who was also Trump’s United Nations ambassador, launching her presidential campaign in February and former Arkansas Gov. Asa Hutchinson, declaring his bid for the Republican nomination earlier this month.

Sen. Tim Scott of South Carolina, another likely contender, launched a presidential exploratory committee earlier this month, while former Vice President Mike Pence said on Sunday he will likely make a decision about entering the GOP primary “well before late June.”