Washington (AFP) - Donald Trump’s signature tax and spending bill was in limbo early Thursday as Republican leaders in the US Congress scrambled to win over a group of rebels threatening to torpedo the centerpiece of the president’s domestic agenda.

Trump is seeking final approval in the House of Representatives for his Senate-passed “One Big Beautiful Bill” – but faces opposition on all sides of his fractious party over provisions set to balloon the national debt while launching a historic assault on the social safety net.

As midnight (0400 GMT) struck, House Speaker Mike Johnson was still holding open a key procedural vote – the bill’s last hurdle before it can advance to be considered for final approval – more than two hours after it was first called.

With no clear sign of the stalemate breaking, his lieutenants huddled in tense meetings behind the scenes with the rebels who had either voted no or had yet to come to the House floor.

“We’re going to get there tonight. We’re working on it and very, very positive about our progress,” Johnson told reporters at the Capitol, according to Politico.

Originally approved by the House in May, Trump’s sprawling legislation squeezed through the Senate on Tuesday by a solitary vote but had to return to the lower chamber Wednesday for a rubber stamp of the Senate’s revisions.

The package honors many of Trump’s campaign promises, boosting military spending, funding a mass migrant deportation drive and committing $4.5 trillion to extend his first-term tax relief.

But it is expected to pile an extra $3.4 trillion over a decade onto the country’s fast-growing deficits, while forcing through the largest cuts to the Medicaid health insurance program since its 1960s launch.

While moderates in the House are anxious that the cuts will damage their prospects of reelection, fiscal hawks are chafing over savings that they say fall short of what they were promised by hundreds of billions of dollars.

Johnson has to negotiate incredibly tight margins, and can likely only lose three lawmakers among more than two dozen who have declared themselves open to rejecting Trump’s bill.

- ‘Abomination’ -

Republican leaders had been hoping to spend just a few hours on Wednesday afternoon green-lighting the package, although they have a cushion of two days before Trump’s self-imposed July 4 deadline.

The 887-page text only passed in the Senate after a flurry of tweaks that pulled the House-passed text further to the right.

Republicans lost one conservative who was angry about adding to the country’s $37 trillion debt burden and two moderates worried about almost $1 trillion in health care cuts.

Some estimates put the total number of recipients set to lose their health insurance at 17 million, while scores of rural hospitals are expected to close.

Legislation in the House has to go through multiple “test” votes before it can come up for final approval, and a majority must wave it through at each of these stages.

There were warning signs early in the day as the package stumbled at one of the first steps, with a straightforward vote that ought to have taken minutes remaining open for seven hours and 31 minutes – making it the longest House vote in history.

Johnson had made clear that he was banking on Trump leaning on waverers, as he has in the past to turn around contentious House votes that were headed for failure.

The president has spent weeks cajoling Republicans torn between angering welfare recipients at home and incurring his wrath.

Trump pressured House Republicans to get the bill over the line in a private White House meeting with several holdouts on Wednesday.

“What are the Republicans waiting for?,” he posted on his Truth Social platform just after midnight.

“What are you trying to prove??? MAGA IS NOT HAPPY, AND IT’S COSTING YOU VOTES!!!”

House Democrats have signaled that they plan to campaign on the bill to flip the chamber in the 2026 midterm elections, pointing to analyses showing that it represents a historic redistribution of wealth from the poorest Americans to the richest.

“Shame on Senate Republicans for passing this disgusting abomination,” House Minority Leader Hakeem Jeffries told reporters.