More than two dozen Republican senators, including Minority Leader Mitch McConnell, are calling on President Joe Biden to withdraw Acting Labor Secretary Julie Su’s nomination to lead the department.

GOP senators accused Su of stonewalling their requests for information on her support for more regulations on gig work in California and a memo sent during her tenure as the state's top labor official that instructed state employees not to cooperate with ICE officials looking for undocumented migrants.

"She has avoided answering questions whenever possible and she has refrained from providing distinct specificity to her answers when she has responded to inquiries," reads the letter, which is led by Sen. Mike Braun, R-Ind. "Given this present state of affairs, we respectfully urge you to withdraw the nomination."

BIDEN'S ‘NIGHTMARE’ LABOR NOMINEE UNDER FIRE FROM SMALL BUSINESSES, CONTRACT WORKERS

A group of 33 GOP senators is pressuring President Biden to withdraw Julie Su's nomination to be Labor secretary.

GOP opposition alone won't be enough to derail Su, but there are signs she may not have enough votes from Democrats in the 51-49 Senate.

Su was narrowly approved by the Senate Health, Education, Labor and Pensions Committee in April, but Senate Majority Leader Chuck Schumer has not yet brought up her nomination for a vote on the floor, which could reflect uncertainty over whether she has the votes.

If Su isn't supported by a majority, she would be the highest-profile nominee yet in a series of progressive Biden nominees who have been pushed out of contention without a vote on the Senate floor.

CALIFORNIA REPUBLICANS URGE BIDEN NOT TO NOMINATE JULIE SU AS LABOR SECRETARY: ‘INCOMPETENCE’

The GOP senators said a lack of cooperation is another reason why Su should be withdrawn. The letter said that Su "refused to be interviewed by HELP Committee minority staff or the staff members representing the Republican senators on the committee, as nominees have traditionally done."

It also highlighted the uncertainty that surrounds the nomination, given that Democrats have not yet called her up for a vote on the floor.

"Despite the nomination of Ms. Su being reported favorably by the committee on a party-line vote on April 26, 2023, and despite the Senate being in session for several weeks since this date, there has yet to be a vote in the full Senate on this nomination. Her track record and unwillingness to provide clarity to her past positions and the actions she would take as Secretary of Labor continue to raise concerns about her nomination," the letter stated.

Republican Indiana Sen. Mike Braun

Sen. Mike Braun, R-Ind., spearheaded the letter on Tuesday. (Tom Williams/CQ-Roll Call Inc. via Getty Images)

In addition to Braun and McConnell, the letter was signed by Senate GOP Whip John Thune, R-S.D., Senate GOP Conference Chair John Barrasso, R-Wyo., and Sen. Tim Scott, R-S.C., among others.

The White House defended Su in a statement to Fox News Digital on Wednesday morning.

"Julie Su is highly-qualified to be Labor Secretary, recently helped secure a labor agreement at the west coast ports, was unanimously confirmed as Deputy Secretary of Labor by all Senate Democrats, and has support from business and labor groups across the spectrum," White House spokesperson Emilie Simons said.

BIDEN TO NOMINATE JULIE SU AS NEXT LABOR SECRETARY

While she’s scored the support of workers’ groups, unions and the White House’s progressive allies, Republicans and pro-business organizations have hammered Su, formerly a civil rights lawyer, for her track record as head of California’s labor board. Under her tenure, the state saw billions of dollars lost to COVID-19 pandemic fraud.

Senator Joe Manchin

Sen. Joe Manchin, D-W.Va., is among the key Democrats whose support or opposition could decide Su's fate. (Gaelen Morse/Bloomberg via Getty Images)

It takes a simple majority vote to confirm a presidential nominee, and Vice President Kamala Harris can act as a tie-breaking vote, if needed. But there are three Democrat-aligned senators who are keeping Su’s nomination in limbo – West Virginia Sen. Joe Manchin, Montana Sen. Jon Tester and independent Arizona Sen. Kyrsten Sinema.

CLICK TO GET THE FOX NEWS APP

None have said how they’ll vote, but all three are facing uphill reelection battles as the GOP eyes their seats in 2024.

Fox News Digital has reached out to the White House for comment but did not immediately hear back.