Eliza Collins and Bartholomew D Sullivan

USA TODAY

WASHINGTON – After Senate Majority Leader Mitch McConnell announced Saturday that he is delaying his plan to consider a bill to replace Obamacare this week, the controversial Republican health care overhaul faces a perilous path forward.

"There are about eight to 10 Republican senators who have serious concerns about this bill," Sen. Susan Collins, a Maine Republican, said on CNN's State of the Union. "So at the end of the day, I don't know whether it will pass."

Republican Sen. John McCain of Arizona will be absent from the Senate this week as he recovers from surgery to remove a blood clot, leading McConnell to announce Saturday night that the Senate would defer consideration of the Better Care Act until McCain returns.

But McConnell now faces a critical task to continue building support for the bill.

Republicans already lost two of their members on the revised bill – the moderate Collins and Kentucky conservative Sen. Rand Paul, who said they would vote against a procedural motion to bring the bill to the floor – and can’t afford to lose a third. Without McCain’s vote in favor, the bill does not have enough support to pass.

Even if the Senate waits for McCain to return and vote to debate the bill, there are more than a half-dozen lawmakers who could be the critical third “no” vote. And those opposed to the bill kept up their drumbeat of criticism on Sunday.

"We should not be making fundamental changes in a vital safety net program... without having a single hearing to evaluate what the consequences are going to be," Collins said.

The bill, Collins said, "would impose fundamental, sweeping changes in the Medicaid program and those include deep cuts. That would affect some of the most vulnerable in our society."

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Sen. Paul also continued to express his concerns about the bill. "I think the longer the bill's out there, the more conservative Republicans are going to discover that it's not repeal. And the more that everybody's going to discover that it keeps the fundamental flaw of Obamacare," he said on CBS's Face the Nation.

"It keeps the insurance mandates that cause the prices to rise, which chase young, healthy people out of the marketplace, and leads to what people call adverse selection, where you have a sicker and sicker insurance pool and the premiums keep rising through the roof," he said. "And one of the amazing things to me is, for all the complaints of Republicans about Obamacare, we keep that fundamental flaw... For all Republicans' complaints about the death spiral of Obamacare, they don't fix it, they simply subsidize it with taxpayer monies, which I just don't agree with at all."

The bill already has drawn opposition from insurance industry trade groups, patients' advocates, doctors, hospitals and some religious groups.

Collins told both ABC’s This Week and CNN's State of the Union that the bill’s proposed cuts to Medicaid would hurt rural hospitals and nursing homes that are also major employers.

Also on CNN, Health and Human Services Secretary Tom Price said that governors are telling him they need the bill to provide flexibility – and justified efforts to lure Alaska’s senators with state-specific provisions unique to their state. He cited Alaska’s landscape – more than 600 municipalities that can’t be reached by road – as justifying special accommodations for Alaska.

Yet on NBC's Meet the Press, Sen. John Cornyn, R-Texas, said the bill contains "no state-specific relief."

"But what there is," he said, "is an an attempt to try to accommodate the concerns of those states that expanded Medicaid under Obamacare and those that did not – and that's the hard task ahead of us."

One key vote lies with Sen. Dean Heller. The Nevada Republican is the most vulnerable GOP senator up for reelection in 2018, in a state Hillary Clinton won during the presidential election.

Heller came out against the original version of the bill in a blistering press conference last month, which was something of a tipping point that ultimately led McConnell to abandon a planned vote before the July Fourth recess. One of Heller’s concerns was scaling back funding for the Medicaid expansion — which his state accepted under Obamacare. That roll back provision stays the same in the new version of the bill.

On Thursday, Heller said he was undecided on the new bill and that he still needed to review it to see how it would impact Nevada.

Meanwhile, Nevada’s Republican governor — who was with Heller when he gave the press conference announcing his opposition to the first version of the bill — said Thursday he was “greatly concerned and very protective of the expansion population,” according to CNN.

Other undecided lawmakers — such as Sens. John Hoeven, R-N.D., Rob Portman, R-Ohio, Shelley Moore Capito, R-W.Va. — said they were holding out final judgement until the nonpartisan Congressional Budget Office released its analysis of the new bill, which is expected early this week.

The CBO review of the previous version found that by 2026 22 million people would be without health coverage, but the bill would reduce the federal deficit by $321 billion over the that same period.

But the White House has already begun mounting an attack on CBO’s credibility, saying its earlier estimates were inaccurate. And it is not clear whether the CBO score will include a critical part of the bill.

A conservative amendment written by Sens. Ted Cruz, R-Texas, and Mike Lee, R-Utah, would legalize the sale of deregulated insurance plans as long as insurance companies also offered at least one plan that includes the coverage mandated under Obamacare.

Fans of the Cruz-Lee Amendment say the deregulated plans will cost less and give people more options but there will also be coverage that includes broader care for people who need it. Critics say younger, healthier people will flock to the deregulated plans leaving older, sicker people to foot higher premiums on the mandated plans.

A late addition to the bill, CBO may not have time to assess the impact of the Cruz-Lee language in its report this week.

And it is not clear the language has even won the vote of Sen. Lee. He said he remained undecided Thursday after the new version of the bill came out because the amendment in the bill was different than what he had written, and it may not go far enough to deregulate the marketplace.

The bill’s chances of passing are so narrow that some Republicans are working on the side to secure an alternative in case the Senate GOP plan fails — and they’re hoping it’ll be bipartisan.

Just minutes before Republican leadership unveiled the new version of the Senate health bill Sens. Lindsey Graham, R-S.C., and Bill Cassidy, R-La., announced the details of their alternative plan. The plan would keep most Obamacare taxes in place and give money back to the states so they can decide how to handle their health care.

“So if a state wants to repair Obamacare they can take the money to repair it, if the state wants to replace Obamacare they can do that,” Graham told reporters Thursday.

Graham has already reached out to at least one Democrat Sen. Joe Manchin of West Virginia. Manchin told USA TODAY Thursday he’d been talking with Graham, but Manchin’s spokesman cautioned that negotiations would not take place until Republicans stop trying to repeal the health care law.

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