Sen Joe Manchin announced on Sunday that he would vote against President Joe Biden's signature Build Back Better Act should it come to the Senate floor, likely guaranteeing that the legislation will never make it to the president's desk.
The shocking announcement came after months of negotiations between Mr Manchin, progressives, and the White House and is a major setback for the Biden administration at a time when the White House is already battling underwater poll numbers and concerns about midterm elections next year.
"I cannot vote to continue with this piece of legislation. I just can't. I've tried everything possible. I can't get there," the West Virginia centrist Democrat told Fox News Sunday guest host Bret Baier.
"You're done? This is a no?" asked Mr Baier in response.
"This is a no," Mr Manchin confirmed.
The news comes days after it was announced that the Democratic-controlled Senate was shifting focus to voting rights legislation, another issue in which Mr Manchin's opposition to changes to the filibuster is expected to doom any attempt at progress.
It also vindicates the views of progressive members of the House who were unwilling to vote "yes" on a smaller, bipartisan infrastructure package until the Build Back Better Act passed for fear that centrists would go back on their vow to continue negotiations, and a blow to those in the progressive caucus who took the White House's word that President Joe Biden could win over Mr Manchin, with whom he publicly touts a warm relationship.
"The president says he can get 51 votes for the bill," House Progressive Caucus chair Rep Pramila Jayapal said last month, adding: "We are going to trust him."
Sen Bernie Sanders, a progressive leader in the Senate and a key supporter of the president's bill, lambasted Mr Manchin as a coward on CNN as the news broke, and urged Senate leadership to bring the package up for a vote anyway to force his colleague to take a public vote against it.
"Well I think he's going to have a lot of explaining to do to the people of West Virginia. Tell him why he doesn't have the guts [to support this bill]," said Mr Sanders.
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