WASHINGTON — Moments before midnight, Senate Republican leaders released text of their 940-page bill on Friday, with the goal of beginning votes on it Saturday.

GOP lawmakers are racing to pass the sweeping package for President Donald Trump’s agenda by a self-imposed deadline of July 4, but it continues to face hurdles along the way. And it’s unclear if Senate Republicans have enough votes to begin debate on it.

The legislation would extend the tax cuts Trump signed into law in 2017 and slash taxes on tips and overtime pay. It includes a $150 billion boost to military spending this year, along with a surge of federal money to carry out Trump’s mass deportations and immigration enforcement agenda. It partially pays for that with cuts to Medicaid, SNAP and clean energy funding, although the legislation is likely to add to the national debt.

It also contains a $5 trillion increase in the debt ceiling ahead of an August deadline to avert a default on the country’s obligations.

With a 53-47 majority in the chamber, Republicans can afford just three defections on the vote, with no hope of winning Democratic support. Republicans are seeking to pass the bill through the budget reconciliation process, which allows them to bypass the Senate’s 60-vote threshold.

Senate Majority Leader John Thune, R-S.D., is aiming to hold a first test vote on the mammoth package Saturday but is running into problems from rank-and-file Republicans who are trying to pump the brakes on the process.

Sen. Ron Johnson, R-Wis., said during an appearance on Fox News Saturday morning that he would vote against the initial motion to start debate on the bill until he has more time to review it.

“We just got the bill, and I got my first copy about 1:23 in the morning, this morning. About 300 provisions, by my count,” Johnson said. “We shouldn’t take the Nancy Pelosi approach and pass this bill to find out what’s in it. We need to know exactly what’s in it.”

Sen. Rand Paul, R-Ky., told NBC News on Friday that he will oppose the bill, but that he would reconsider if Republicans strip out the debt ceiling hike. That is highly unlikely to happen. Paul, the only GOP senator who has voted against the measure throughout all the steps of the process this year, said it is “much more of a spending bill than a bill that rectifies the debt problem.”

The GOP package prohibits Medicaid funding for entities that provide abortions, including Planned Parenthood, seeking to make good on a long-standing conservative priority. But that pursuit has faced opposition from Sens. Susan Collins, R-Maine, and Lisa Murkowski, R-Alaska, so the provision could imperil their votes.

Leaving the Capitol on Friday night, Thune said he’s not certain that Republicans have the votes to advance the measure but that it’s time to act.

“It’s a process and hopefully the votes will be there,” Thune said, “but we won’t know for sure until we actually have the vote.”

Even if the package can pass its first hurdle Saturday, it would still have a long way to go. There would be at least 10 hours of debate before senators can start voting on amendments, and Democrats are threatening to force the reading of the entire bill. The House, which passed its own version in May, would need to pass the Senate bill before it heads to Trump’s desk.

GOP leaders are making daring bet that reluctant members won’t vote to scuttle Trump’s “big, beautiful bill” when push comes to shove. And they’ve said they may need to enlist the president to twist arms and sway holdouts.

The Senate legislation seeks to resolve a standoff over the state and local tax (SALT) deduction. It lifts an existing $10,000 cap to $40,000 for five years — down from a decade in the House-passed version — before lowering it back to $10,000. That represents a significant concession for blue-state House Republicans who had insisted on solidifying the higher cap.

The bill seeks to mitigate the pain of Medicaid cuts on some providers by creating a rural hospital fund worth $25 billion over five years. It includes work requirements and other new rules for recipients to qualify.

Senate Minority Leader Chuck Schumer, D-N.Y., slammed the bill.

“At the behest of Big Oil, in the dead of night, Senate Republicans released a new version of their ‘Big, Beautiful Betrayal’ that retroactively raises taxes on energy,” he said in a statement Saturday. “Republicans want to jack up your electric bills and jeopardize hundreds of thousands of jobs, all so they can give billionaires tax breaks.”