Two Senate committees on Wednesday delayed votes on President Biden’s nominee to lead the Office of Management and Budget, as the White House continued to struggle to find the votes to secure her passage through the Senate.

The Senate Homeland Security and Governmental Affairs Committee and the Senate Budget Committee abruptly postponed votes on Neera Tanden scheduled for Wednesday.

Tanden’s nomination has appeared increasingly in jeopardy over the past week as Sen. Joe Manchin III (D-W.Va.) and a number of moderate Republican senators announced they would not vote for her, probably dooming her selection in an evenly divided Senate.

One key GOP senator — Sen. Lisa Murkowski (R-Alaska) ― is still vetting Tanden’s nomination and has not yet decided how she will vote, a spokeswoman said.

Murkowski told reporters that she has not spoken with Tanden yet but that she has spoken with White House officials who had offered to make her available for a conversation. In a tweet from 2017, Tanden appeared to tell Murkowski that the Alaska senator must be “high on your own supply” after Murkowski tweeted support for lowering the corporate tax rate. Shown the tweet on Wednesday, Murkowski asked: “Should I ask her my own supply of what?”

“That goes to show how much homework I still have to do on her,” Murkowski said. “I suggested to the White House that my colleagues were being very critical of the statements, and rightly so — I think clearly some of them were over the top.”

Murkowski also said the White House’s case for Tanden amounted to the fact that she was the president’s selection but was not substantive beyond that.

The White House budget office is at a pivotal juncture, tasked with writing Biden’s budget and overseeing the disbursal of the president’s $1.9 trillion coronavirus relief package, once Congress passes it.

Many of the same Republicans who turned a blind eye to Donald Trump's controversial tweets slammed OMB director nominee Neera Tanden for her Twitter history. (Drea Cornejo/The Washington Post)

The White House continued to defend Tanden’s candidacy on Wednesday despite the obstacles. Manchin and Republican lawmakers have raised concerns about her now-deleted tweets criticizing GOP senators, but the administration has praised her as a policy expert well suited to lead the budget office.

“Neera Tanden is a leading policy expert who brings critical qualifications to the table during this time of unprecedented crisis,” White House press secretary Jen Psaki said on Twitter on Wednesday morning. “She has a broad spectrum of support, ranging from the U.S. Chamber of Commerce to labor unions, and has a strong record of working with both parties that we expect to grow in President Biden’s cabinet as the first South Asian woman to lead OMB.”

Still, chatter has grown among White House allies and on Capitol Hill about a replacement to lead the agency.

Shalanda Young, a former Appropriations Committee staff member nominated by Biden as deputy director of OMB, has emerged as one leading candidate and probably is the front-runner, according to two people who spoke on the condition of anonymity to share discussions among senior Democrats. Numerous congressional aides of both parties, who spoke on the condition of anonymity to describe internal dynamics, predicted that Young would be quickly approved if chosen.

Other names White House allies have discussed in recent days include Ann O’Leary, who served as chief of staff to California Gov. Gavin Newsom (D); Gene Sperling, an economic aide in the Clinton and Obama administrations; Martha Coven, a former OMB official under President Barack Obama who helped lead the search for Biden’s OMB team; and Sarah Bianchi, a longtime Biden policy aide, the people said.

The Congressional Black Caucus has been planning a letter to the White House supporting Young, a Black woman, for the position, should Tanden’s nomination be pulled. Sen. Richard C. Shelby (Ala.), the highest-ranking Republican on the Senate Appropriations Committee, also expressed support for Young on Wednesday.

“I believe [Young] would be good in that role. She’s smart, she knows the process inside-out, and she’s an honest broker who has demonstrated the ability to work with both sides and get things done,” Shelby said in a statement. “She would have my support, and I suspect many of my Republican colleagues would support her, as well. But that’s up to the Biden administration.”

Sen. Bernie Sanders (I-Vt.), chairman of the Budget Committee, spoke with Tanden on Tuesday night before the delay was announced, according to one person who spoke on the condition of anonymity to share details of the private conversation. Sanders and Tanden clashed repeatedly during his presidential primary campaigns, and the White House declined to consult Sanders on the Tanden nod for OMB during the transition, The Washington Post previously reported. Sanders has not said how he would vote on Tanden.

Senate Republicans continued to criticize the administration over the selection.

“This administration has a lot of experienced people in it, and I was surprised that red flags did not go off, or that they weren’t raised when Neera Tanden was first discussed,” Sen. Susan Collins (Maine) said.

Sen. John Thune (S.D.), the second-ranking Senate Republican, said he believes there is “if not unanimous, near unanimous opposition to her nomination.”