Several Republican lawmakers are fuming over President Donald Trump’s elevation of Stephen Miller to be his chief of staff.

"Horrible decision," Rep. Marlin Stutzman, R-Ind., told Fox News Digital on Friday after Trump announced his decision.

A Republican lawmaker who was granted anonymity to speak candidly said they were in "utter disbelief." Tensions were rising against Miller in the wake of Republicans’ terrible performance in Tuesday’s midterm elections. Multiple House Republicans who spoke with Fox News Digital just moments before his promotion said Miller, who spearheads Trump’s immigration policy, should be fired.

When later asked about his promotion, one House Republican who said Miller should be fired replied simply with a facepalm emoji.

Republicans suffered historic losses that saw both the House and Senate fall into Democrats’ hands in the new Congress. Democrats are on pace to win more than 250 seats in the House and at least 54 in the Senate.

AMERICA SAW THE BLUE WAVE COMING — BUT DRASTICALLY UNDERESTIMATED THE EXTENT OF THE DEM TSUNAMI And while voter analyses have shown that Trump’s war in Iran and tariffs played the biggest roles in turning people away from the GOP, his handling of illegal immigration served to alienate voters in key areas. That’s in no small part due to Hispanic and Latino voters turning their backs on Republicans in places like Texas that shifted massively toward Democrats in this election cycle.

"Because of his immigration positions, I just think we ruined a lot of our goodwill with Latino voters," Stutzman said.

The second GOP lawmaker told Fox News Digital that Miller ignored multiple warnings from House Republicans in the past, arguing that Trump’s immigration crackdown is what voters asked for.

"I've been in several group meetings where a lot of us have told him, ‘Your immigration enforcement policies are backfiring back home, our people are mad, our businesses are mad — even in deep red districts — and it is impacting not just the voters, but the donors, and everybody top to bottom," that GOP lawmaker said. "But it looked to me like Stephen Miller was only after numbers … he would not listen to us." Other Republicans who spoke with Fox News Digital also criticized Miller but did not go as far as to say he should be fired.

"I think he's greatly hurt the administration and cost us many seats on Tuesday," retiring Rep. Don Bacon, R-Neb., told Fox News Digital before news of Miller’s promotion broke. "He took an immigration policy that favored the president 2:1 in the public, over-reached and made it 2:1 unfavorable." "Many Republicans don’t like him," Bacon added when asked about his promotion.

Miller is widely known as Trump’s right hand on immigration policy, including earlier this year when the administration faced bipartisan backlash over its handling of anti-immigration enforcement protests in places like Minneapolis.

Several Republicans, particularly those running in battleground districts, had called for Trump to limit deportations to illegal immigrants who have committed crimes while in the United States.

A fourth GOP lawmaker said, "Stephen is a megalomaniac who should have never been given the keys to the Ferrari. That being said, he's not the reason why we lost...no one knows who Stephen Miller is in our districts." Various other administration officials also got their share of blame in the fallout from Tuesday’s midterm massacre, including Secretary of War Pete Hegseth and Trump himself.

But the president and people in his orbit have blamed candidate quality, arguing that in many cases the president campaigned harder than some of the people he supported did for themselves.

And in his Truth Social post announcing Miller’s promotion, Trump called him one of his "most trusted advisors." He later told reporters Miller would "do a great job."

When Fox News Digital reached the White House for comment, spokeswoman Lauren Bis said Miller "has been a key player in delivering on President Trump’s America First agenda since day one." "He has spearheaded the administration’s crime crackdown including in D.C. and Memphis, record setting deregulation, unleashed American energy, dismantled drug cartels, and secured our border. In his new role, he will continue to deliver historic successes for the American people," Bis said. Bis also pointed to a list of positive comments about Miller by administration officials and members of Congress.

"Very grateful to Susie for her friendship and service to the president and our country. Stephen Miller is an amazing patriot and will do great things. Congrats to him on a well deserved promotion!"

Vice President JD Vance said. "Stephen Miller has built a proven record focused on securing our border, combating crime, and advancing a now much-needed common-sense conservative agenda for our country," House Freedom Caucus Chairman Andy Harris said.

A White House official told Fox News Digital Miller had experience working with Democrats on the D.C. Safe and Beautiful Task Force and that he has been a "valuable, trusted aide" since 2016.