(WASHINGTON) — Opposition to Julie Su as President Joe Biden’s next labor secretary, and the reluctance of some Democrats to back her, has put her nomination in doubt as she faces a confirmation hearing Thursday.

Sens. Joe Manchin of West Virginia and Jon Tester of Montana are Democratic holdouts and their opposition could derail Su’s confirmation vote in the 51-49 Senate.

Her nomination is further put in question by the absence of Democratic Sen. Dianne Feinstein, who is sidelined recovering from shingles and unable to vote.

Time is dwindling for the Biden administration and Senate Democratic leaders to persuade Manchin and Tester — along with independent Sen. Kyrsten Sinema — to consider approving Su, formerly California’s top labor official, as Biden’s choice to replace Marty Walsh.

Walsh left the administration in March in order to head up the National Hockey League Players Association.

Su will appear before the Senate HELP committee on Thursday, facing what is likely to be a turbulent confirmation process.

The Los Angeles native was narrowly confirmed on a party-line vote in 2021 to become Walsh’s deputy secretary of labor. Tester, Manchin and Sinema, who voted to confirm Su at that time, all now face competitive reelection races in 2024 and appear to be distancing themselves from Biden.

“My vote for her last time was all predicated on Marty,” Manchin told Politico last month.

Republican critics oppose Su’s labor policy record in California and her oversight of the disbursement of unemployment benefits across the state during the pandemic — a process they say was marked by fraud.

But Su, a first-generation Chinese American who would be the only Asian American member of Biden’s Cabinet if confirmed, has robust support from most Asian American organizations, immigrant rights advocates and women’s groups.

She also has backing from much of organized labor, which has said “well-heeled lobbyists and corporate special interests are spending big to block her confirmation.”

“What stands out about Su, beyond her expertise in labor law and policy, is that she believes so deeply in what she does,” the AFL-CIO, the nation’s main labor federation, said in a statement.

“Prior to her predecessor, it had been decades before workers even had a union member at the helm of the Labor Department,” the union added.

Of the 606 nominees Biden has picked for his administration, 511 have been confirmed so far, with 93 nominations pending in the Senate, according to the Washington Post’s appointee tracker.

But Su is hardly the first nomination snarl the Biden administration has had in recent months.

Several important judicial nominations have been delayed due to Feinstein’s absence from the Senate Judiciary Committee.

Some Democrats have have called on her to resign while Senate Democrat Leader Chuck Schumer and Judiciary chairman Dick Durbin have attempted to replace her on the committee — a move Senate Republicans have blocked.

Phil Washington withdrew his name as Biden’s nominee to head the Federal Aviation Administration after he was unable to shore up Democratic support. Sinema and Tester had expressed reservations.

Also last month, Federal Communications Commission nominee Gigi Sohn withdrew after ​​Manchin announced he would vote against her.

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