A sprawling budget bill in the US Senate could cut health insurance coverage for nearly 12 million Americans and add $3.3tn (£2.4tn) in debt, according to new estimates.
The assessment from the Congressional Budget Office, a non-partisan federal agency, could complicate Republican efforts to pass President Donald Trump’s One Big Beautiful Bill Act in the coming days.
The spending plan narrowly cleared a preliminary vote in the Senate late on Saturday after party leaders scrambled to arm-twist hesitant members of their rank and file.
One defector, Senator Thom Tillis of North Carolina, announced he would not seek reelection after voting against the president’s signature legislation.
Democratic lawmakers have led criticism of the bill. The CBO numbers calculate $1tn in cuts to healthcare funding if the measure passes.
The latest version of the bill was advanced in a 51-49 Senate vote on Saturday night. Two Republicans – Tillis and Rand Paul of Kentucky – joined Democrats in opposing the move.
Paul has said he opposes the bill because it raises the US debt limit. Tillis has said the bill would cost his state billions of dollars in healthcare funding.
While senators debated the bill on Sunday, it is unclear whether it has enough support to ultimately pass.
Republicans have a small majority in the Senate, holding 53 seats. Vice-President JD Vance has the tie-breaker vote so the party can only afford three defectors.
Democratic senators used chamber rules to force a 16-hour reading of the nearly 1,000-page bill in an attempt to delay a vote on its passage.
Under Senate rules, lawmakers now have 20 hours allocated to debate the bill. It is expected that Democrats will use all of their time to further delay a vote, while Republicans try to speed up the process.
Lawmakers could also propose amendments to the bill. If the revised bill passes the Senate, it still must return to the House of Representatives for final approval before landing on the president’s desk for signing into law.
Trump has pushed for the bill to clear Congress before a self-imposed 4 July deadline. The White House said failure to pass it would be the “ultimate betrayal”.
On Saturday, he called the Senate’s vote to advance the bill a “great victory”.
But the bill’s proposed cuts to Medicaid, a healthcare programme that is relied on by millions of elderly, disabled and low-income Americans, have become a political flashpoint.
Democratic Senator Mark Warner told CNN on Sunday that the measure would negatively affect millions. “This is tax cuts for the wealthiest to end up cutting healthcare, plain and simple,” he said.
Under the bill, more than 80% of Americans would get a tax cut next year, though wealthier taxpayers would benefit most, including as a percentage of income, according to the non-partisan Tax Policy Center.
Senator Markwayne Mullin, an Oklahoma Republican, told NBC on Sunday that the legislation aims to eliminate fraud, waste and abuse.
He argued that many Americans using Medicaid are not under the poverty line.
“We don’t pay people in this country to be lazy,” he said. “We want to give them an opportunity. And when they’re going through a hard time, we want to give them a helping hand.”
Some parts of the spending bill were revised in the Senate in order to appease Republican holdouts.
It still contains some of its core components: tax cuts that Trump campaigned on, such as a tax deduction on Social Security benefits, and the elimination of taxes on overtime work and tips.
It would also extend tax cuts passed by Republicans in 2017.
The bill proposes cuts to certain programmes in order to pay for the tax deductions.
On healthcare, the spending bill proposes a work requirement on most adults in order to qualify for benefits.
It also reduces the amount of taxes that states can charge medical providers, the funds from which are used heavily to finance Medicaid programs.
After some Republican senators voiced concern that these cuts would hurt rural hospitals in their districts, lawmakers added a provision in the latest bill that increases the size of a rural hospital relief fund from $15bn to $25bn.
The bill includes restrictions on the US food stamps programme, by asking most adults with children 14 or older to show proof of work in order to qualify.
It also shifts some costs from the federal government to states starting in 2028.
