WASHINGTON Hours after releasing their health care proposal , Senate GOP leaders were trying to tamp down a mutiny within their ranks, with various Republicans criticizing the legislation from different perspectives and for different reasons.

Some GOP senators hate the proposed Medicaid cuts. Some believe the cuts take too long to take effect. Some think the tax credits still need to do more to help people pay for health insurance. And at least one, Sen. Rand Paul of Kentucky, said the bill needs to eliminate more of the subsidies.

It needs to look more like a repeal and less like keeping Obamacare, Paul told reporters Thursday, after he and Sens. Mike Lee (R-Utah), Ted Cruz (R-Texas), and Ron Johnson (R-Wis.) released a joint statement saying they were not ready to support the legislation.

While they all said they were willing to negotiate, opening the bill up for the changes they want could further throw in doubt the votes from the small core of moderate Republican senators, whose backing already is shaky.

This is Senate Majority Leader Mitch McConnells fundamental problem: The Kentuckian seeks a just right Goldilocks compromise that splits the difference between his partys moderates and conservatives. His problem? He can only lose two votes to pass his bill , given unified opposition from the 48-member Democratic caucus.

Giving in to Cruzs demands to allow states to opt out of certain Obamacare regulations like those that protect the insurance coverage for people with preexisting conditions would almost certainly cost him votes from moderates who may already be leaning against the legislation. Caving to moderates who want even milder Medicaid funding cuts endangers the support from those conservatives already concerned that the reductions take seven years to fully kick in.

If McConnell were a few votes closer to the 50 he needs (with Vice President Mike Pence ready to break a tie in the 100-seat chamber, if needed), his current position would be potentially less perilous. But as of now, he appears well short of that striking distance, with at least four conservatives announcing their public disapproval and at least four of the GOP moderate expressing concerns over the Medicaid cuts.

For every change McConnell accepts for conservatives, theres a chance moderates move further away from supporting the bill. And vice versa.

Still, McConnell is a master arm-twister, and everything could come together quickly for him. It was notable that even as Johnson was saying Thursday he thinks the Senate may consider starting over, he told HuffPost that the bare minimum it would take to get to a yes may simply be proper information.

Sen. Susan Collins of Maine has looked like one of the most unlikely GOP supporters of the bill from the beginning, and she stressed Thursday her concerns about the formula for how the government calculates how much it gives to states for Medicaid.

It is lower than the cost of medical inflation and would translate into literally billions of dollars of cuts, Collins said. And that would mean states would be faced with unpalatable [choices], such as restricting eligibility for the program and allowing rural hospitals to go under.

That may seem like a serious concern and it is. But its also one of those fixes that could be made if McConnell and President Donald Trump can get enough other Senate Republicans to agree to the overall bill in principle.

A basic problem McConnell faces is that polls show the push to repeal and replace Obamacare faces problems with much of the public. And the more people learn about the specifics of repeal effort which has a fundamental aim of cutting taxes for the rich and significantly reducing the number of people served by Medicaid the less likely voters are to be swayed by heated rhetoric that merely slams Obamacare.

Again, though, that is not to say Senate Republicans wont ultimately go along with their leaderships bill.

The opposition looks soft, save perhaps for Paul. GOP conference chairman Sen. John Thune of South Dakota said Thursday he didnt think Paul, despite saying he wanted to work with leadership on the legislation, would ever be there in the yes camp.

Igor Bobic contributed to this report.