Many Republican senators dismissed the idea of overruling the Senate parliamentarian after she rejected key Medicaid provisions in Trump's tax and immigration bill Thursday, which dealt a blow to Republicans' plan to slash costs in the budget package.

This sentiment comes as Senate Majority Leader John Thune has said for months that he was opposed to going against the Senate's rule enforcer.

Senate Parliamentarian Elizabeth MacDonough on Thursday denied the GOP plan to cap states' ability to collect more federal Medicaid funding through health care provider taxes -- a controversial provision that would have funded much of the bill's tax cuts. Most of the savings in the bill came from the changes in Medicaid.

MacDonough's ruling means that Senate Republicans will need to retool the provision or scrap it entirely if they want to move forward with attempting to pass the bill using only GOP votes.

The ruling is a major setback for Republican leadership, who are under pressure to expeditiously move it to the Senate floor to meet Trump's Fourth of July deadline for passage. This ruling will require potentially major reworks of the bill with relatively little time to accomplish them. And no matter how they change it, leaders are likely to frustrate some faction of the Republican conference, which could imperil the bill's passage.

Meanwhile, Speaker Mike Johnson said the House is "on a wait and see basis" as the Senate continues to make changes to the bill.

The speaker said the Senate Medicaid ruling “doesn’t make it easier” for the bill to pass by the July 4 deadline.

“But you know me, hope springs eternal. And we are going to work around the clock to try and meet that deadline.”

Johnson suggested he could “make a case” for overruling the parliamentarian.

“If only that were our decision,” he said. “The senators have to make that call. I mean, I can make a case for it, but no one's asking.”

A number of Senate Republicans said on Thursday morning that they'd work to tweak language in the bill and send it back to MacDonough for review -- but would not overrule her. It's also unlikely that the Senate would move forward with the bill without the provider tax provisions, some said.

The Senate has "no intention of overruling her," Republican Sen. Lindsey Graham said of MacDonough. "But I think we'll take another shot."

Other Republican senators said that this will delay the timeline for passing the bill, which was set to move through the chamber this weekend.

"I think we'll make another run at it … my guess is that they'll continue to work," Republican Sen. Eric Schmitt said.

"Yeah, could push [the timeline] back," Schmitt said about MacDonough's ruling. "We'll see. But we're committed to being here through the weekend, so I don't think it changes that overall time frame."

Republican Sen. Rick Scott said MacDonough's ruling is "pretty frustrating," but rejected the idea that the Senate would overrule the parliamentarian.

"What we've got to do is work through this process and come up with something that fulfills the Trump agenda -- also has fiscal sanity. So I'm going to keep working hard to do that," Scott said, adding he's "optimistic" it can be accomplished.

Republican Sen. John Kennedy stated clearly that "we would never overrule the parliamentarian."

Other Republicans fumed over the parliamentarian and her ruling.

Republican Sen. Tommy Tuberville came out brashly against MacDonough -- calling for Thune to fire her "ASAP" and accused her of being partisan. He did not mention overruling her, however.

"The WOKE Senate Parliamentarian, who was appointed by Harry Reid and advised Al Gore, just STRUCK DOWN a provision BANNING illegals from stealing Medicaid from American citizens. This is a perfect example of why Americans hate THE SWAMP," Tuberville said in a post on X.

"Unelected bureaucrats think they know better than U.S. Congressmen who are elected BY THE PEOPLE. Her job is not to push a woke agenda. THE SENATE PARLIAMENTARIAN SHOULD BE FIRED ASAP," he added.

Republican Sen. Markwayne Mullin suggested that MacDonough made her rulings as part of a "political decision."

"I'm concerned about the parliamentarian's ability to make these decisions," Mullin said.

He later added, "If it's a political decision on [her] part, then that's not OK."

The provider tax credit provisions had been emerging as a thorn in leadership's side even before MacDonough's ruling.

For days, a small but critical faction of the Senate GOP conference had been raising major flags about the way this cut to states' Medicaid revenue might kneecap rural hospitals in their states. A number of Republicans in the Senate were threatening to withhold their votes for the package because of these changes to the provider tax, so for that group, MacDonough's ruling is likely a welcome one.

If changes are made to the provision, all eyes will be on a handful of Senate Republicans. Some changes could be deal breakers for those whose vote is critical to moving the bill over the finish line.

Last weekend, MacDonough carefully scrutinized the House-passed bill for possible violations of the Senate's rules. She has already issued a number of decisions that Democrats are touting as major victories.

This review, called the Byrd Bath -- named after the late Sen. Robert Byrd, who helped institute the rules governing budget reconciliation packages, is still underway in the Senate.

Any provision that MacDonough rules out of order with the Senate's rules will have to be stripped or else the legislation will be subject to the 60-vote threshold in the Senate. Republicans need to avoid this, or they won't be able to pass the bill.