By Nadine Yousif, BBC News

Senate Republicans narrowly advanced President Donald Trump’s sweeping budget proposal—nicknamed the “Big Beautiful Bill”—on Saturday, bringing it a step closer to a vote ahead of the self-imposed 4 July deadline.

In a tense 51-49 vote, the Senate agreed to open debate on the nearly 1,000-page bill, overcoming the first major hurdle in the legislative process. While most Republicans fell in line, two—Senators Rand Paul of Kentucky and Thom Tillis of North Carolina—broke ranks and sided with Democrats in opposition.

Party leaders worked intensely behind the scenes to secure support, releasing the latest version of the bill just after midnight. With Vice-President JD Vance standing by to cast a tie-breaking vote, leadership ultimately managed to clinch a majority without needing him.

The bill, which passed the House of Representatives by a single vote last month, has become central to President Trump’s second-term policy agenda. It proposes extending $3.8 trillion in tax breaks first enacted during Trump’s 2017 term and introduces new deductions—including for Social Security benefits, overtime pay, and tipped income.

But the legislation has sparked division among Republicans, particularly over proposed cuts to welfare programs. Some moderates expressed concerns about potential impacts on vulnerable constituents, while fiscal hawks objected to provisions they see as too generous.

To win over hesitant lawmakers, the Senate version of the bill includes targeted revisions—such as increased funding for rural hospitals and modifications to the Supplemental Nutrition Assistance Program (SNAP). Notably, Alaska and Hawaii would be temporarily exempt from a provision that shifts some SNAP funding responsibilities to state governments, a concession to Alaska’s Republican senators.

Despite these changes, the bill continues to include controversial reforms to Medicaid. Democrats have condemned the proposed restrictions and eligibility requirements, warning that millions could lose healthcare coverage. The Congressional Budget Office estimates that 7.8 million Americans would become uninsured if the cuts are enacted.

“This bill contains the largest healthcare cuts in U.S. history,” Senator Patty Murray (D-WA) wrote on social media, echoing widespread Democratic opposition.

Senate Minority Leader Chuck Schumer vowed to delay proceedings as long as possible, pledging that Democrats would force the Senate to read the entire 940-page bill aloud before moving forward with debate.

The bill has also drawn criticism outside the political sphere. Tech entrepreneur Elon Musk blasted the measure on social media, claiming that new taxes on renewable energy projects would “destroy millions of jobs” and weaken the U.S. strategically.

President Trump, meanwhile, took to Truth Social to lash out at Senator Tillis for his “NO” vote, calling it a “BIG MISTAKE” and hinting at supporting a primary challenger against him.

Still, several previously skeptical Republicans—including Senators Lisa Murkowski of Alaska and Susan Collins of Maine—ultimately backed the bill. Senator Ron Johnson of Wisconsin even changed his vote at the last minute, flipping from “no” to “yes.”

With Republicans holding 53 Senate seats and a potential tie-breaking vote from Vice-President Vance, the GOP can afford no more than three defections in the final vote. While Saturday’s vote marks progress, the final passage of the “Big Beautiful Bill” remains far from certain.