Two down, one to go.

The brand-new Republican bill to replace Obamacare ran into a huge, old problem right away Thursday when two GOP senators who had problems with the original version said they would vote against the new legislation.

The solid opposition by Rand Paul of Kentucky and the qualified opposition by Maine’s Susan Collins means that if just one other Republican senators declares they will vote “no” on the revised bill, it will likely be dead in the water.

Paul said that he will vote against the new bill.

Collins said she will vote against putting the bill on track to passage “unless I learn something new.”

And at least five other senators reportedly indicated Thursday that they are undecided on whether to vote for a motion that would allow the bill to head for a final vote by the Senate.

There are just 50 other Republican senators besides Collins and Paul.

To pass the bill, the GOP needs at least 50 yes votes from senators, with the understanding that Vice President Mike Pence, a Republican, would cast a tie-breaking vote. Every one of the 48 Democratic senators and two independents are expected to vote against the bill.

It was opposition by Collins and other moderate Republicans in the Senate, along with opposition from conservatives such as Paul of Kentucky, that caused GOP leaders to rewrite their bill after realizing the original version had no chance of passing.

“At this point, unless I learn something new, I am a ‘no’ on [the] motion to proceed,” Collins said, according to NBC News.

Republican leaders have said they will hold a vote on a motion to proceed with their bill next week, after a Congressional Budge Office analysis of it is released. If that motion fails, the bill will not be able to proceed for consideration.

If the motion passes, senators would then be able to offer amendments to the bill.

Collins said that for her to support the bill, a CBO analysis expected to be released next week would have to show that there would be less of a negative effect on the nation’s Medicaid program than the original version of the bill would have had.

Collins added that she does not think the CBO would make such a finding.

The CBO, in analyzing an earlier version of the bill, estimated that it would lead to 22 million more Americans lacking health insurance by 2026 than if the current law remained in place. Millions of those people would have otherwise had health coverage through Medicaid, a government-run program that serves primarily poor people.

Republican leaders have struggled for weeks to craft a bill that will please conservative senators, who favor an aggressive repeal of Obamacare, while at the same time getting support from moderates, who oppose cuts to Medicaid and Planned Parenthood.

Sen. Marco Rubio, R-Fla., said Thursday that he wants to make sure that the bill would benefit residents of his state before deciding whether to vote for it.

Rubio added that it would be difficult to support a bill that would punish a what he called a fiscally-responsible state such as Florida.