Sen. John McCain (R-Ariz.) dealt a critical blow to Republicans' last-ditch attempt to roll back the Affordable Care Act on Friday, announcing that he could not "in good conscience" vote for sweeping repeal legislation that GOP leaders plan to bring to the Senate floor next week.
Echoing concerns he raised over the summer when he helped defeat an earlier repeal bill in a dramatic late-night vote, the senior Arizona senator also delivered a stern rebuke of his party's attempt to push through the large, complex measure with little public scrutiny, only one hearing planned and no support from Democrats.
"We should not be content to pass healthcare legislation on a party-line basis," McCain said in a lengthy statement criticizing the GOP.
"I take no pleasure in announcing my opposition. Far from it. The bill's authors are my dear friends," he said, referring to Sens. Lindsey Graham (R-S.C.) and Bill Cassidy (R-La.). "I hope that in the months ahead, we can join with colleagues on both sides of the aisle to arrive at a compromise solution that is acceptable to most of us, and serves the interests of Americans as best we can."
McCain's move raises serious questions about whether Republicans have the votes to advance their latest repeal effort, which only days ago seemed to be gaining considerable momentum.
The party, which has 52 votes in the Senate, can lose only two more Republicans, or the bill will fail, even with Vice President Mike Pence's ability to cast a tiebreaking vote.
Already Sen. Rand Paul (R-Ky.) has said he would oppose the bill, which he complained maintains too much of the current law's government spending on healthcare.
"I won't vote for Obamacare Lite that keeps 90% of the taxes & spending just so some people can claim credit for something that didn't happen," Paul tweeted Friday. "Calling a bill that KEEPS most of Obamacare 'repeal' doesn't make it true. That's what the swamp does. I won't be bribed or bullied."
Sens. Susan Collins of Maine and Lisa Murkowski of Alaska, two centrist Republicans who joined McCain to help sink the GOP repeal effort in July, have signaled strong reservations about the current proposal.
"I'm leaning against the bill," Collins said at an event in Maine, according to the Portland Press Herald newspaper.
Senate Majority Leader Mitch McConnell (R-Ky.) did not immediately respond to McCain's announcement or signal how he would proceed next week.
McConnell had indicated he wanted to put the Graham-Cassidy proposal to a vote next week, as Republicans face a Sept. 30 deadline under Senate rules to be able to advance a repeal bill with only 50 votes. After that, the threshold rises to 60 votes.
The Graham-Cassidy proposal, which first emerged over the summer, was initially dismissed by many GOP senators, but the end-of-month deadline and pressure from the party's conservative base to fulfill the repeal pledge has prompted a scramble by Senate Republican leaders and the White House to round up the votes to revive their push.
President Trump and Vice President Pence have been calling senators for days trying to build support. And GOP leaders have been offering various sweeteners to win votes, such as more money for specific states, including Alaska.
"Rand Paul, or whoever votes against Hcare Bill, will forever (future political campaigns) be known as 'the Republican who saved ObamaCare,'" Trump tweeted Friday.
Pence met Friday morning with Maine Gov. Paul LePage, a Republican, while calling on Collins to support the bill. And the vice president conducted a round of Alaska radio interviews Thursday urging listeners to prod their senators to back Graham-Cassidy, even though that state's governor opposes the bill.
Because of the close friendship between McCain and Graham, many Republicans had remained hopeful that the Arizona senator could be convinced to support the new effort. Arizona Gov. Doug Ducey, a Republican, also threw his support behind the Graham-Cassidy bill.
But the proposal has generated a storm of opposition in recent days from patient advocates, hospitals, physician groups and a growing number of healthcare experts.
Public opposition is also substantial, with a new ABC News/Washington Post poll showing that Americans by more than a 20-point margin prefer the existing law to the current GOP repeal bill.
Every significant independent analysis of the proposal has calculated that it would lead to huge cuts in federal healthcare aid, which, in turn, would probably erode health insurance coverage for tens of millions of Americans.
On Friday, the National Assn. of Medicaid Directors, who run state safety net programs that would see huge cuts under Graham-Cassidy, called on Congress to slow down and consider the bill more carefully.
"Any effort of this magnitude needs thorough discussion, examination and analysis, and should not be rushed through without proper deliberation," the bipartisan group said.
The centerpiece of the latest GOP bill is a new system for distributing hundreds of billions of dollars of federal money that would restructure how the government provides healthcare assistance to some 80 million Americans.
The bill would effectively end both the current Medicaid program, which covers poor Americans, and the system of insurance subsidies made available by the 2010 Affordable Care Act, known as Obamacare, to help low- and moderate-income consumers buy health plans.
It would mark the biggest change in how the nation's healthcare is financed in more than 50 years.
In place of these programs, the federal government would give states blocks of money to redesign their healthcare safety nets, while also capping future federal support for states.
Graham and Cassidy have said the expanded flexibility would allow states to create better, cheaper programs. But there is much debate about that claim.
Passing the legislation next week would require lawmakers to vote before the independent and nonpartisan Congressional Budget Office has had a chance to analyze its impact, particularly on insurance coverage and premiums.
"Without a full CBO score, which won't be available by the end of the month, we won't have reliable answers to any of those questions," McCain noted Friday.
McCain instead called on his colleagues to return to the bipartisan process that had been underway in the Senate Health Committee to develop compromise measures to help stabilize insurance markets around the country.
Committee Chairman Lamar Alexander (R-Tenn.), who had been leading that effort, abruptly announced this week that he was stopping it, apparently in an effort to drive support to the Graham-Cassidy bill.
Democratic leaders echoed McCain's call to reconvene bipartisan negotiations to improve the Affordable Care Act.
"John McCain shows the same courage in Congress that he showed when he was a naval aviator," said Senate Minority Leader Charles E. Schumer (D-N.Y.) "I have assured Sen. McCain that as soon as repeal is off the table, we Democrats are intent on resuming the bipartisan process."
The committee's senior Democrat, Sen. Patty Murray of Washington, has also called on Alexander to return to the negotiating table to deliver something that both parties can support.
2:45 p.m.: This article was updated with additional reaction and analysis.