Washington — Senate Minority Leader Mitch McConnell, who has openly criticized former President Donald Trump for years, endorsed him for president on Wednesday, one day after Trump's slew of victories on Super Tuesday brought him closer to the GOP nomination.

The vocal detractor of the former president said in a statement that "it is abundantly clear that former President Trump has earned the requisite support of Republican voters to be our nominee for President of the United States." 

"It should come as no surprise that as nominee, he will have my support," McConnell said, noting that during Trump's first term, the two leaders worked together to "accomplish great things for the American people."

The endorsement came one week after McConnell announced he would step down from Senate GOP leadership at the end of the year. 

The endorsement reflects Trump's clear path toward cementing the nomination, one that became clearer with Nikki Haley's decision to drop out of the race earlier in the day. With the endorsement, McConnell becomes the last of the top GOP congressional leaders to coalesce behind the former president. And if Trump can win McConnell's backing, despite a deep rift between the two men and their approach to leading the GOP — along with weighty personal grievances — little stands between Trump and total sway over the party. 

Trump thanked McConnell for the endorsement in a social media post on Wednesday.

"Thank you, Mitch," the former president wrote. "I look forward to working with you and a Republican Senate MAJORITY to MAKE AMERICA GREAT AGAIN!"

The relationship between Trump and McConnell reached its low point after the Jan. 6, 2021, attack on the Capitol. At the time, McConnell spoke out fiercely against Trump, although he ultimately voted to acquit Trump in his second impeachment trial. 

"Former President Trump's actions that preceded the riot were a disgraceful, disgraceful dereliction of duty," McConnell said on the Senate floor after the chamber voted to acquit Trump. "There is no question — none — that President Trump is practically and morally responsible for provoking the events of the day."

In an opinion piece in the Wall Street Journal in February 2021, McConnell said of Trump, "His behavior during and after the chaos was also unconscionable, from attacking Vice President Mike Pence during the riot to praising the criminals after it ended."

Adding to the enmity, Trump has repeatedly mocked McConnell's wife, Elaine Chao, often using racist language to describe his Taiwan-born former transportation secretary. Chao resigned the day after the Jan. 6 attack on the Capitol. 

The endorsement comes as the Kentucky Republican's grip on his conference has seemed to slip in recent months, after 17 years at the helm. 

When the bulk of McConnell's conference quickly rejected a bipartisan Senate-negotiated border security agreement at Trump's urging in recent weeks, McConnell relented, noting that the dynamics had changed. And although McConnell succeeded days later in getting enough of his conference behind a foreign aid bill that includes funding for Ukraine, one of his key priorities, the chapter elicited some of the most vocal opposition yet to McConnell's continued leadership. 

Though his endorsement of Trump may appear to be a reversal, McConnell previously made clear that he would eventually back the Republican nominee regardless of his own reservations, citing his role as the Senate GOP leader. When asked by reporters about the endorsement at the Capitol on Wednesday, McConnell reiterated that pledge. 

"I said in February of 2021, shortly after the attack on the Capitol, that I would support President Trump if he were the nominee of our party and he obviously is going to be the nominee of our party," he said.

Kaia Hubbard

Kaia Hubbard is a politics reporter for CBS News Digital based in Washington, D.C.

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