Holdouts among Senate Republicans could sink Trump's agenda bill after its narrow passage from House

Senate Republicans said Thursday that they are eager to delve into President Trump’s “big, beautiful bill” and begin to make their own changes to the House-passed legislation by the July 4 weekend.

Republicans, who control the Senate with a 53-47 seat majority, will deploy their legislation through the budget reconciliation process as a way to avoid needing 60 votes and thus Democratic support.

Any changes that are made to the legislation, though, means the measure is sent back to the House for further debate and another vote.  

The bill, which is the centerpiece of President Trump’s agenda, includes sweeping spending cuts and tax cuts for all Americans. It prevents the largest tax increase in history by stopping the 2017 Trump tax cuts from expiring. The legislation also provides funding for border security and national defense, and measures to spur American energy production.

However, three Republicans can sink it if they vote against the measure and Sens. Susan Collins of Maine and Lisa Murkowski of Alaska have taken issue over the legislation’s position on Medicaid and Sen. Josh Hawley of Missouri has said he would not support any bill that slashed the program.

“I have said and made clear that I do not want to take away Medicaid benefits, which would not only hurt low-income families, but also our rural hospitals,” Ms. Collins said. “In particular, I am for work requirements for able-bodied individuals, as long as they’re carefully drafted.”

Sen. Rand Paul of Kentucky opposes the bill as it stands, though he told reporters Thursday he could vote for the package if a provision to raise the debt ceiling were removed from it.

“The anticipated deficits per year now will be 2 trillion a year for the next two years. So it’s not conservative, and I can’t support it,” Mr. Paul said. “If they were to take the debt ceiling off of it and have the tax reductions and the spending reductions, I’d probably vote for that.”

Other Republicans are looking to make changes in other places, including Thom Tillis of North Carolina, who said he was seeking to make relief on business expensing permanent.

Sen. Ted Cruz said he was pleased with the measure, specifically the provisions on school choice and Invest America, calling them both “transformational.”

He also called to keep investment accounts in the bill, which includes Opportunity Zone designations and related tax incentives.

Mr. Trump urged the Senate, in all-capital letters, to get the bill to his desk “as soon as possible!”

“This is arguably the most significant piece of Legislation that will ever be signed in the History of our Country!” he posted on social media.

The 215-214 House vote capped a week of uncertainty as more than a dozen Republicans threatened to oppose the bill over various concerns when GOP leaders could afford to lose no more than three.

“We’re delivering, and we’re doing it in a big way,” said House Speaker Mike Johnson, Louisiana Republican. “To our friends in the Senate, I would just say the president is waiting with his pen. The American people are waiting for this relief.”

Ultimately, just two Republicans voted against the bill — Reps. Warren Davidson of Ohio and Thomas Massie of Kentucky — and one, Rep. Andy Harris of Maryland, voted “present.”

All three were concerned about the measure’s impact on the deficit, with Mr. Massie panning it as a “debt bomb ticking.”

The Congressional Budget Office estimates the bill would add $3.8 trillion to the deficit over 10 years, which most Republicans argue significantly undercounts the economic growth it will spur from tax cuts and regulatory rollbacks.

• Lindsey McPherson contributed to this report.