Senate Republicans on Saturday took a crucial step toward passing their sweeping domestic policy bill, voting 51-49 to start debate on the legislation.

Two GOP senators — Rand Paul of Kentucky and Thom Tillis of North Carolina — joined Democrats to oppose advancing the cornerstone of President Donald Trump’s second-term agenda. But several others came around after hours of last-ditch negotiations to keep the bill moving forward.

The vote came after a daylong scramble by GOP leaders to win over several Republican senators who were viewed as undecided or had vowed to block debate over their opposition to pieces of the bill — including an extended negotiating session that unfolded with various senators while the vote was underway.

Now the chamber is on track to pass the bill sometime Monday. Democrats are forcing Senate clerks to first read the legislation out loud, which is expected to happen overnight, before a maximum 20 hours of debate plus a marathon series of amendment votes.

“Fifty-three members will never agree on every detail of legislation, let’s face it. But Republicans are united in our commitment to what we’re doing in this bill,” Majority Leader John Thune said shortly before the vote. “It’s time to get this legislation across the finish line.”

Trump personally intervened Friday and Saturday to shore up the whip count. He reached out to Tillis on Friday night, according to a person granted anonymity to disclose private conversations. Tillis later confirmed the call, telling reporters he told Trump he could not support the bill because of the Medicaid language. Trump later attacked Tillis publicly and called for him to face a Republican primary challenger.

Sen. Ron Johnson of Wisconsin and Sen. Rick Scott of Florida were at the White House shortly before the Senate’s vote. Johnson initially voted no, then went into a long stretch of negotiations with Thune, Vance and others alongside Sens. Mike Lee of Utah, Cynthia Lummis of Wyoming and Rick Scott of Florida. In the end, they emerged and voted to advance the bill just after 11 p.m.

By Saturday afternoon, it was clear to GOP senators that Vice President JD Vance would need to be on standby for what would be a nailbiter. He interceded after the vote was called to win over Alaska Sen. Lisa Murkowski, and then went to work on the other holdouts.

While enough GOP senators have voted to start debating the bill, it’s not yet assured there will be enough to pass it. Pieces of the bill remain in flux — not only due to Senate concerns, but also lingering opposition from some House Republicans. Several key issues, including the state-and-local-tax deduction and key Medicaid language, were addressed in updated text released late Friday night. But negotiations continues as leaders in both chambers work to ensure the Senate product can be passed in the House without changes and sent immediately to Trump’s desk.

Already GOP leaders have agreed to delay implementation of changes to a key Medicaid provision — a new cap on medical provider taxes, which most states use to fund their Medicaid programs — and have increased a rural hospital assistance fund from $15 billion to $25 billion.

Those changes were sufficient to win over Sen. Josh Hawley (R-Mo.), who announced Saturday he would support the bill. But it wasn’t enough to sway holdouts in both chambers concerned that the health care language could lead to hospital closures in their states and districts.

While Sen. Susan Collins of Maine supported starting debate, she described herself as “leaning against” final passage if the Medicaid provisions don’t change before a final vote. Collins said she planned to offer several amendments reflecting her concerns.

“It is the majority leader’s prerogative to determine which bills to bring to the floor,” she told reporters. “That does not mean in any way that I’m satisfied with the provisions in this bill.”

Tillis told reporters that he would be a “no” on the final vote, barring dramatic changes to the Medicaid provisions.

“It would result in tens of billions of dollars in lost funding for North Carolina, including our hospitals and rural communities,” he said in a statement. “This will force the state to make painful decisions like eliminating Medicaid coverage for hundreds of thousands in the expansion population, and even reducing critical services for those in the traditional Medicaid population.”

Johnson, Paul and Scott had each raised sharp concerns about the bill’s fiscal impacts, arguing it needed to cut more government spending. Paul, in particular, was deadset against its inclusion of a $5 trillion hike to the federal debt ceiling.

GOP leaders had more success putting out another fire: Sen. Tim Sheehy (R-Mont.) warned shortly before the vote that he would not support opening debate because of a provision in the bill providing for the sale of public lands. About 40 minutes after delivering that ultimatum, he said in an X post he would instead seek to amend the bill and remove the provision.

Republicans also made changes in the draft text released overnight to more aggressively phase out clean-energy tax credits established under former President Joe Biden in a bid to win over House conservatives. That prompted new attacks on the bill from Elon Musk, the erstwhile Trump ally, who called the megabill “utter madness” and “political suicide for the Republican Party.”

Democrats are expected to use the marathon amendment process, known as vote-a-rama, to try to water down the bill’s changes to the energy provisions, as well as Medicaid, federal food assistance and other key social safety net items.But first Democrats want to slow things down. By forcing clerks to read the 940-page bill aloud — a process that is typically waived — they hope to win more time to draw attention to the bill’s most unpopular provisions.

Senate aides estimate reading could take about 15 hours, pushing final passage from Sunday into Monday unless Democrats unexpectedly yield back a significant amount of their debate time.

President Donald Trump said he would explore backing a primary challenger to two-term Sen. Thom Tillis Saturday — just hours after the North Carolina Republican voted against advancing the centerpiece of Trump’s legislative agena.

Trump berated Tillis in mutiple Truth Social posts, saying he was making a “big mistake” and that he would be meeting potential primary challenges as he was “looking for someone who will properly represent the Great People of North Carolina.”

Tillis has long expressed concerns about the impact of Medicaid changes in the bill on North Carolina and said Saturday he would not support the legislation unless changes are made. Trump did not mention the issue in his posts, but did detail Tillis’ earlier concerns with preserving some clean-energy tax breaks that Republicans are targeting.

North Carolina is the top pickup opportunity for Senate Democrats in 2026, and Tillis is a veteran of multiple tough races in the Tarheel State. In 2014, as speaker of the state House, he knocked off incumbent Kay Hagan in one of the closest Senate races of the cycle. Tillis then won narrowly in 2020 after his Democrat opponent, former state Sen. Cal Cunningham, got himself embroiled in a sexting scandal.

Tillis was already anticipating facing a strong Democratic opponent next year: Former Rep. Wiley Nickel has already announced a Senate bid, and popular former Gov. Roy Cooper is also mulling a run.

A Senate vote on advancing Republicans’ party-line domestic-policy bill has been held open for more than two hours as GOP leaders scramble for the final votes.

Vice President JD Vance arrived at the Capitol shortly after 8 p.m. to break a possible tie. Three Republican senators — Ron Johnson of Wisconsin, Rand Paul of Kentucky and Thom Tillis of North Carolina — have already voted “no.” A fourth GOP opponent would at least temporarily sink the megabill and likely foil plans to get it to President Donald Trump’s desk by July 4.

Senate Majority Leader John Thune, Majority Whip John Barrasso, Finance Chair Mike Crapo and Budget Chair Lindsey Graham are meeting off the floor with Vance, Johnson and the three Republican holdouts — Sens. Mike Lee of Utah, Cynthia Lummis of Wyoming and Rick Scott of Florida. The three are believed to be voting as a bloc; Lee and Scott have raised concerns about the level of spending cuts in the bill.

“We need more deficit reduction,” Lee said before the vote. Notably, he announced Saturday night he was dropping a provision to sell some public lands from the megabill amid intraparty opposition.

Thune was tight-lipped heading into the meeting saying only, “It’s a long vote.”

Earlier in the evening, Sen. Lisa Murkowski of Alaska made her fellow Republicans sweat, withholding her vote for nearly an hour while a gaggle of key leaders surrounded her on the Senate floor.

Murkowski, who had already secured major concessions for her home state, spent more than a half-hour in deep and sometimes animated conversations with Crapo, Graham, Barrasso and Thune, also talking separately to Sens. Bill Cassidy of Louisiana and John Curtis of Utah. At one point she held Vance’s hand while she talked with him one-on-one in the back of the chamber.

Graham could be heard loudly saying that to “start the process” would be “best.” Eventually she voted to move forward with the bill, with a big smile, but only after she retreated into the cloakroom for additional conversations with leaders and committee chairs.

Lisa Kashinsky contributed to this report.