6 Senate Republicans who could hold up Trump's 'big, beautiful bill'

Senate Republicans will take control of the party’s mammoth tax and domestic policy bill when they return to Washington on Monday — and seek to win over a diverse group of GOP lawmakers agitating for changes to the legislation.

Members are staring down a key four-week stretch to hammer out provisions of the bill, with their Fourth of July goal in sight and pressure mounting to complete President Trump’s top domestic agenda priority. 

The bill narrowly passed the House last month after Speaker Mike Johnson (R-La.) struck a fragile compromise with different factions of his conference.

But there are still Senate Republicans who could gum up the works as Senate Majority Leader John Thune (R-S.D.) works to shepherd the legislation through the upper chamber with only three votes to spare.

Here’s a look at a half-dozen of those lawmakers to watch in the coming weeks. 

Sen. Lisa Murkowski (R-Alaska)

Murkowski, one of the foremost Senate GOP moderates, is atop the list of the members Thune and his leadership team will have to win over, and she has already indicated she has a number of concerns.

Although Murkowski voted for the Senate GOP’s budget resolution — which served as the blueprint for the bill — in early April, she told reporters she was worried about three items.

Among those is the impact of potential Medicaid work requirements, as she believes her state will have trouble implementing them due to its outdated payment systems for the program. 

“There are provisions in there that are very, very, very challenging if not impossible for us to implement,” Murkowski said.

She has also expressed worries about what the Medicaid changes could mean for tribal communities in her state, which are heavily reliant on Medicaid for health coverage. 

On top of that, she and three of her colleagues have expressed concerns with language in the House bill that would nix wind, solar and geothermal energy tax credits that were put in place by the Inflation Reduction Act. 

Sen. Josh Hawley (R-Mo.) 

He’s not a name that usually ends up on these lists, but Hawley has been perhaps the most vocal member of the Senate GOP conference about potential cuts to Medicaid benefits.

He has maintained that the Medicaid cuts are a red line for him in backing the final package — even as conservatives in the House have shown an interest in taking a hatchet to the health care program.

And he has a key player in the entire effort seemingly on his side.

“We ought to just do what the president says,” Hawley told reporters last month after the House passed the bill.  

Two days earlier, Trump had told House Republicans in a closed-door meeting to “leave Medicaid alone.”

Hawley added that he spoke with Trump about the state of play. 

“His exact words were, ‘Don’t touch it, Josh,’” Hawley told reporters. “I said, ‘Hey, we’re on the same page.’” 

Hawley has also shown a willingness to take that stand on the floor. During the chamber’s first vote-a-rama in February, Hawley sided with Democrats on an amendment that would have prevented tax cuts for wealthy Americans if Medicaid funding is slashed.

Any cuts to Medicaid beneficiaries would hit the Show Me State hard in particular given that 21 percent of Missourians rely on the program or the Children's Health Insurance Program, the companion insurance program for lower-income children. 

Sen. Susan Collins (R-Maine) 

Collins stands out as one of only two Republicans — along with Sen. Rand Paul (R-Ky.) — to vote against the party’s budget resolution in April, though she is the far more likely of the two to vote “aye” when push comes to shove on final passage. 

The Maine Republican has continuously expressed opposition to reductions in federal Medicaid funding and shifting costs to the states, sounding the alarm on the effect doing so would have on her state’s rural hospitals. Maine’s rural hospitals intensely rely on the health care program, and cuts could deal a crippling blow, she argues.

Collins cited that issue in her vote against the budget blueprint, and she has kept up the drumbeat.

"Medicaid is a critically important program for Maine's health care system and a vital resource for many seniors, low-income families, disabled patients, and those who cannot work,” Collins said in a statement at the time. “I cannot support proposals that would create more duress for our hospitals and providers that are already teetering on the edge of insolvency.”

She said last week, on the eve of the House passing the measure, that “we’re still trying to figure out what the provider tax reforms are, but I’m very worried about our rural hospitals in Maine.”

Collins was also the only other Senate Republican to vote with Hawley and Democrats for the vote-a-rama Medicaid amendment in February.

Her up-in-the-air standing is nothing new for the GOP, especially on a single-party effort. Eight years ago, Collins was a split decision on the GOP’s two reconciliation bills.

She voted alongside Murkowski and the late Sen. John McCain (R-Ariz.) against the party’s plan to repeal the Affordable Care Act. Months later, though, she backed the Tax Cuts and Jobs Act. The GOP’s current tax agenda would likely make those 2017 cuts permanent.

Sen. Rand Paul (R-Ky.)

If there’s one Republican senator who is the most likely to oppose the package at the end of the day, it’s Paul.

The Kentucky Republican has been a loud critic of the bill over its inclusion of a debt ceiling hike and lack of deficit reduction.

Paul has made clear that his red line for any bill is a debt ceiling increase. But Republicans on both sides of the Capitol are seemingly intent on following through on Trump’s wishes to include it and help the party avoid giving Democratic concessions in any possible negotiation. 

This means that without any changes, Paul will be a “no,” and Senate GOP leaders have less breathing room than they had hoped, capping their votes at 52 in the process. 

“I’ve told them if they’ll take the debt ceiling off of it, I’ll consider voting for it,” Paul said last week after the House vote about his talks with GOP leadership. “It’s not conservative; I can’t support it.”

“The spending reductions are imperfect, and I think wimpy, but I’d still vote for the package if I didn’t have to vote to raise the debt ceiling,” he added.

Sen. Ron Johnson (R-Wis.) 

Senate GOP leaders have long had to worry about the concerns of moderates, but it’s Johnson and his fellow conservatives who are making their complaints known over what they view as unacceptable levels of cuts.

Johnson has not gone nearly as far as Paul in saying he is prepared to oppose a final bill, but he has hinted that conservatives may throw their weight around.

“We need to be responsible, and the first goal of our budget reconciliation process should be to reduce the deficit,” Johnson told CNN last weekend. “This actually increases it.” 

“I think we have enough [senators] to stop the process until the president gets serious about the spending reduction and reducing the deficit,” Johnson added. 

Johnson has been vocal about his desire to see greater spending reductions, pointing to the roughly $4 trillion the bill would add to the deficit in its current form.

He has voiced a preference to move toward pre-COVID spending levels, arguing that this is the U.S.’s last chance to do so. 

Sen. Thom Tillis (R-N.C.)

Tillis, a moderate-leaning senator eyeing what could be a close reelection race in 2026, has aired multiple points of concern, headlined by the axing of energy tax incentives in the bill.

He has told colleagues that the swift termination of the credits enacted by the Inflation Reduction Act will cause major harm to numerous companies in North Carolina and force them to scramble after years of planning.

He pointed specifically to former President Biden’s abrupt killing of the Keystone XL Pipeline four years ago and how it has left investors second-guessing whether to back similar projects.

“A wholesale repeal, or the termination of certain individual credits, would create uncertainty, jeopardizing capital allocation, long-term project planning, and job creation in the energy sector and across our broader economy,” Tillis, Murkowski and Sen. John Curtis (R-Utah) wrote to Thune back in early April.

Adding to the drama for Tillis, he is staring down one of the two most contentious Senate races on the 2026 map, forcing him to shore up potential weak points as Democrats look to pounce — and giving leadership an incentive to hand him a win for his voters back home.