Manchin won’t support Raskin for the Fed, imperiling her nomination.

If she cannot secure all the Democratic votes, though, the issue is likely moot.

“Now that it’s clear Sarah Bloom Raskin has no path to confirmation, it’s time for the Senate Banking Committee to proceed with the other four nominees, as committee Republicans have been pushing for weeks,” Senator Thom Tillis, Republican from North Carolina, wrote Monday on Twitter.

Besides Mr. Powell, who goes by Jay, Mr. Biden has nominated Lael Brainard to be the Fed’s vice chair and two academic economists — Philip Jefferson and Lisa Cook — to be governors.

“This effectively kills her nomination,” Tobin Marcus at Evercore ISI wrote after the news, adding that it “likely clears the way for Biden’s other Fed nominees — Jay Powell, Lael Brainard, Lisa Cook and Philip Jefferson — to advance and be confirmed.”

The Senate has only ever confirmed one vice chair for supervision at the Fed, Randal K. Quarles, whom President Donald J. Trump nominated. Before Mr. Quarles, Daniel Tarullo, a Fed governor, unofficially served in the role for years. The position was created by the 2010 Dodd-Frank Act.

The White House made it clear on Monday that it was still focused on finding Republican votes for Ms. Raskin’s nomination, and other prominent Democrats continued to hold out hope.

“The way out is to get some Republicans to support her,” said Senator Elizabeth Warren of Massachusetts, who sits on the Banking Committee and has been a proponent of Ms. Raskin’s. “They all supported her the last two times she was nominated. She’s been at the Fed; she’s been at the Treasury.”

But the centrist Republican senators who might have been seen as likely sources of support for Ms. Raskin — including Senators Lisa Murkowski of Alaska and Susan Collins of Maine — said on Monday that they would not support her. Ms. Murkowski called her candidacy “flawed.” While Ms. Collins said she spoke to Ms. Raskin on Monday, she said “I think it is evident from Joe Manchin’s statement this morning that there is not a path forward for her.”