President-elect Trump's latest selection for his next administration is facing immediate backlash from some within the Senate GOP, as they say his attorney general pick, Rep. Matt Gaetz, R-Fla., will not get confirmed. 

"He will never get confirmed," a Republican senator, granted anonymity to speak freely, told Fox News Digital. 

One Senate Republican source simply said, "Ain’t gonna happen," about the prospect of Gaetz's confirmation. 

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Rep. Matt Gaetz, R-Fla.

Republicans told Fox News Digital that Rep. Matt Gaetz, R-Fla., will not get confirmed. (Aaron Schwartz/NurPhoto via Getty Images)

Gaetz's office referred Fox News Digital to his response on X, "It will be an honor to serve as President Trump’s Attorney General!" and did not comment on the GOP criticism about his potential confirmation. 

Sen. John Cornyn, R-Texas, told reporters, "I think we have to consider any nominee by the president seriously, but we also have a constitutional responsibility." 

He was prompted about whether the House Ethics investigation currently being conducted into Gaetz would factor in to his confirmation, to which the senator replied: "That might come up."

The allegations being probed by the committee include sexual misconduct, illicit drug use and accepting improper gifts. 

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Donald Trump, Matt Gaetz split

President-elect Trump announced his selection of Gaetz on Wednesday. (Getty )

Responding to the announcement of Gaetz's selection for attorney general, Rep. Michael Guest, R-Miss., who chairs the Ethics Committee, said that "once a member is no longer a member of Congress, then ethics has no jurisdiction. So if Matt Gaetz were to be appointed as the Attorney General, the ethics investigation [which] is currently ongoing would cease at that point."

However, Senate Republicans were not explicitly supportive. "He’s under investigation by the House Committee on Ethics," Sen. Susan Collins, R-Maine, acknowledged. "Obviously, the president has the right to nominate whomever he wishes, but this is why the background checks that are done by the FBI and the advice and consent process in the Senate, and public hearings are also important."

"He will go through the nomination process just like everyone else," said Sen. James Lankford, R-Okla.

Sen. Katie Britt, R-Ala., told reporters, "I got nothing for you on that," when asked about Trump's choice.

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Sen. Susan Collins, R-Maine

Sen. Susan Collins, R-Maine, noted the importance of the Senate's advice and consent on nominations.  (Samuel Corum/Getty Images)

"I think what we can tell you right now is that we always allow the President to have the benefit of the doubt, but we still have to do our role in terms of due diligence," said Sen. Mike Rounds, R-S.D., when asked if he would vote to confirm Gaetz. 

In addition to the ethics investigation, Gaetz was at one point being investigated by the Department of Justice (DOJ) in a yearslong probe into sex trafficking allegations. But last year, Gaetz's office said the DOJ ended their investigation and determined he would not be charged with any crimes. 

While Republicans could very well be poised not to confirm Gaetz, who has proven controversial among his own party, Trump could look to appoint him through a recess appointment. The president-elect made an appeal to Senate Republican leader candidates earlier this week, telling them they must agree to allow him to make such appointments. 

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Sen. John Thune at a news conference

Sen. John Thune, R-S.D., didn't commit to Trump's request for recess appointments. (Eric Lee/Bloomberg via Getty Images)

Senate Minority Whip John Thune, R-S.D., who won the leader election on Wednesday morning, signaled being open to this in an exclusive statement to Fox News Digital. However, he didn't commit to it. 

"We must act quickly and decisively to get the president’s cabinet and other nominees in place as soon as possible to start delivering on the mandate we’ve been sent to execute, and all options are on the table to make that happen, including recess appointments," he said. 

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If Trump were successful in appointing a cabinet member through a recess appointment, they would be able to serve in the role for nearly two years, according to the Congressional Research Service. The appointment would expire once the next session of Congress, following the recess, adjourns. 

"Recess appointments expire at the end of the next session of the Senate," according to a recent CRS report. "As a result, a recess appointment may last for less than a year or nearly two years, depending on when the appointment is made."