There could be as many as six Republican senators opposed to the One Big Beautiful Bill Act, enough to sink the legislation in the upper chamber, dealing a massive blow to the signature legislation of President Donald Trump's second term.

Sens. Rand Paul of Kentucky and Thom Tillis of North Carolina have stated their intent to vote against the bill, meaning the GOP can only lose one more vote to get the measure passed because Democrats are steadfastly opposed.

At least a half-dozen Republicans were still undecided Monday, The New York Times reported, because several issues that could make or break their decisions had not been resolved.

Senators were still waiting to see if the parliamentarian would allow a number of provisions aimed at winning the vote of Sen. Lisa Murkowski, R-Alaska, to be part of the bill, including one that would exempt her state from having to fund a share of nutrition assistance payments financed entirely by the federal government. Murkowski has been vocal about how the legislation would hurt her state.

Sens. Rick Scott of Florida, Ron Johnson of Wisconsin, Mike Lee of Utah, and Cynthia Lummis of Wyoming have demanded a vote on an amendment that would slash Medicaid further, by changing the formula used to determine what share of the program's bills are paid by the federal government.

Johnson has said he will wait to see whether Republicans adopt that amendment before deciding whether he will support the overall legislation. Should the proposal succeed, the bill could lose the support of senators who are alarmed at the level of Medicaid cuts it would impose, as well as Republicans in the House in districts with large populations of Medicaid beneficiaries.

Also, Sen. Susan Collins, R-Maine, who has not committed to voting for the bill, planned to offer an amendment to raise the tax rate for the most affluent Americans back to what it was before the 2017 tax cuts were enacted. Collins has said she is unhappy that the legislation does not contain a bigger fund to help rural hospitals absorb the Medicaid cuts laid out in the bill.

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