WASHINGTON – The Senate embarked on a freewheeling process to rewrite the Affordable Care Act on Tuesday, as Republicans overcame deep divisions to bring their proposals up for debate by the narrowest possible margin.

But those same schisms threatened to leave the party far short in the coming days of its ambitious goal to undo major parts of the ACA, which the Republican Party has been vowing for seven years to dismantle. On Tuesday night, just hours after opening debate, Senate Republican leaders failed to pass a bill that they spent weeks crafting but never gained sufficient traction with the rank-and-file.

Fifty-seven senators, including both from Maine, opposed the measure known as the Better Care Reconciliation Act, while 43 supported it, portending a difficult road ahead for the Republican rollback effort.

The earlier vote to begin debate marked a momentary political victory for Senate Majority Leader Mitch McConnell, R-Kentucky, and President Trump. The president managed to resuscitate the Republican Party’s months-long effort to unwind President Obama’s signature 2010 law by convincing more than half a dozen wavering senators that they could not afford to walk away from an enduring political promise. Republicans passed the procedural hurdle by a slim 51-50 vote margin, with Vice President Pence breaking the tie.

Steve Butterfield, policy director for the Maine nonprofit advocacy group Consumers for Affordable Health Care, said senators were voting to open debate despite not knowing what version of Obamacare repeal would be brought before them. But all versions, he said, would rip health care away from millions.

“Shocked, horrified and disappointed are all words that come to mind,” Butterfield said.

Moderate Sens. Susan Collins, R-Maine, and Lisa Murkowski, R-Alaska, were the only Republicans to defect from their party’s quest in the initial vote that kept repeal alive. Their complaints about the legislation had included its cuts in Medicaid, the health insurance program for the poor, the disabled and nursing home residents. Opening debate on the Republican bill was opposed by all Democratic senators.

“She (Collins) has been an absolute profile in courage for the past few months,” Butterfield said. “She had talked about bipartisan solutions when no one else was willing to touch that topic.”

Butterfield also praised Maine Sen. Angus King, an independent who caucuses with the Democrats, for being a frequent and outspoken critic of efforts to repeal the ACA.

King, in a statement after the vote, said, “Today, the Senate has moved forward to consider misguided legislation, any version of which will hurt millions of people across the country and tens of thousands of hardworking people across Maine. I’ve never seen a process like this before with no hearings and it will almost certainly produce a terrible bill that will drastically raise costs for people in Maine, put coverage out of reach for many others, and reduce Medicaid funding, causing states to choose between helping seniors or children or people with disabilities. As the Senate advances with this bill, I will continue to support and protect people in Maine and work to find solutions that keep people covered and make health care more affordable.”

U.S. Rep. Chellie Pingree, a Democrat representing Maine’ 1st District, said in a statement, “Today’s vote was an act of cowardice by Republican leadership, many of whom have refused to address the concerns of their constituents – the people who will feel the consequences of this bill in the most personal of ways.

“It doesn’t matter how you slice it. Whether the Senate takes up repeal and delay or its own version of Trumpcare, today’s vote brings millions of Americans closer to losing their insurance coverage and, for millions more, skyrocketing premiums. If the Senate does move forward with a bill, I will fight it tooth and nail in the House as so many Mainers have asked me to do,” Pingree said.

The health-care debate is likely to spark a chaotic, unpredictable couple of days on Capitol Hill — with senators voting on everything from abolishing much of the law to what is being called a “skinny repeal.” The result of these ensuing votes, many think, will be far more modest changes to the ACA than the party has long advertised.

“The endgame is to be able to move something at the end of this process across the Senate floor that can get 50 votes and then to get into conference with the House,” said Sen. John Thune, R-S.D., a top McConnell lieutenant.

Tuesday’s proceedings were marked by high drama, including the return of Sen. John McCain. R-Ariz., to the Capitol just 1½ weeks after undergoing surgery for brain cancer, and Pence’s move to cast the tiebreaking vote. The intensity of the debate, including protesters who yelled “Kill the bill!” in the Senate chamber after the voting had begun, underscored the stakes involved in overhauling a health-care system that affects one-sixth of the nation’s economy and how tens of millions Americans receive medical care.

SEN. CRUZ VERSION OF PLAN BLOCKED

When the Senate voted Tuesday evening on the bill’s initial amendment, according to The Associated Press, it underscored how hard it will be for the chamber’s divided Republicans to pass a sweeping replacement of Obama’s law.

By 57-43 – including nine Republican defectors – it blocked a wide-ranging proposal by McConnell to erase and replace much of the statute. It included language by Sen. Ted Cruz, R-Texas, letting insurers sell cut-rate policies with skimpy coverage, plus an additional $100 billion to help states ease out-of-pocket costs for people losing Medicaid sought by Midwestern moderates such as Rob Portman, R-Ohio.

Earlier in the day, in a sign of how muddled the situation remains, McCain took to the floor after voting to move ahead and declared, “I will not vote for the [Senate leadership bill] as it is today. It’s a shell of a bill right now.”

Sen. Jerry Moran, R-Kan., echoed these sentiments, tweeting, “I support a full repeal of Obamacare & will continue to oppose the BCRA,” referring to the leadership bill called the Better Care Reconciliation Act.

Trump has been pushing aggressively for Republicans to pass a repeal-and-replace plan, saying that opposing the procedural motion to proceed with debate would be tantamount to endorsing the law known as Obamacare.

Speaking Tuesday at a joint news conference in the Rose Garden, the president said he is “very, very sad” for the Republicans who opposed the motion but “very happy with the result” of the vote.

“Now we’re all going to sit together and try to come up with something really spectacular,” he said. “It’s a very, very complex and difficult task, something I know quite a bit about.”

Now, Senate Republican leaders plan to move ahead with votes they hope will culminate at the end of the week in the passage of at least narrow changes to the ACA that will become the basis for negotiations with the House. This “skinny repeal” strategy would keep the overhaul effort alive but amount to a tacit acknowledgment that broader efforts to revise or repeal the law cannot succeed, even as Republicans control both Congress and the White House.

“They expect us to tackle the big problems,” McConnell said on the Senate floor, referring to American voters. “So all we have to do today is to have the courage to begin the debate. . . . Let the voting take us where it will.”

The “skinny repeal” option would repeal the ACA’s mandates that individuals buy plans and that employers with 50 or more employees provide coverage, said lobbyists and Senate aides, and would eliminate the law’s tax on medical device manufacturers.

DEMOCRATS DECRY PARTISAN PROCESS

Democrats signaled that they won’t stand in the way of plans to vote on different versions of the legislation.

“These votes, frankly, are a lot tougher for them than they are for us. They are squeezed in both directions,” Senate Minority Leader Charles Schumer, D-N.Y., told reporters.

Sen. Richard Durbin, D-Ill., the party’s top vote-counter, acknowledged that some Democrats might support Republican-written amendments to the bill that have bipartisan support. But he said that Democrats will focus mostly on process over policy, and keep pushing Republicans to return the legislation to committee and proceed with regular procedure. There have been bipartisan complaints that the legislation was drafted – by McConnell and a handful of leaders – without enough transparency.

Recognizing their lack of leverage inside the chamber, Senate Democrats decried Republicans’ policies and procedural approach in a rally with supporters just outside the Capitol. “How about we fill the streets outside every Republican office in America?” said Sen. Jeff Merkley, D-Ore.

Several patient-advocate organizations and progressive groups decried the vote to begin debate, warning that it could open the door to rollbacks in the expanded coverage the ACA has provided through new benefits requirements and greater federal support for insurance coverage.

“Republican leaders are using undemocratic and unprecedented means to rob coverage and critical services from millions of women, sending them back to a time when women’s health care services were not considered essential,” Nancy Northup, president and chief executive of the Center for Reproductive Rights, said in a prepared statement.

BARTERING FOR REPUBLICAN SUPPORT

Meanwhile, Nathan Nascimento, vice president of the conservative group Freedom Partners, urged senators to use the votes to partly repeal the law and then keep pushing for full repeal. “And then use the next available opportunity to keep their promise by repealing the rest of Obamacare, including its costly regulations and choice-stifling mandates,” he said.

But one key way Senate leaders managed to win Tuesday’s procedural vote was by assuring several centrist Republicans that they may end up with a modest bill.

McConnell and his deputies were still bartering with a handful of Republican holdouts in the hours leading up to the vote. Among the skeptics were about half a dozen Republicans from states that expanded their Medicaid programs under the ACA to cover able-bodied adults and low-income parents earning up to 138 percent of the federal poverty level.

Although it was clear that some, such as Collins, were unlikely to support McConnell’s repeal plan, Portman and Sen. Shelley Moore Capito, R-W.Va., remained in talks with leaders until the final days.

The group has met regularly since talks started earlier this year, and they have generally banded together to ward off conservative demands that the bill slash funding for Medicaid. The group was largely quiet in the days leading up to the vote, but Sen. John Cornyn, R-Texas, said he thinks leaders won them over with a spate of last-minute bartering, including a pledge to include Portman’s amendment.

That provision would add $100 billion more in federal funding to help consumers with out-of-pocket medical costs, said senators and aides, and would allow states to provide cost-sharing assistance to low-income people who transition from Medicaid to buy private insurance with a federal tax credit.

“They’ve been very diligently working to make sure their concerns were addressed,” Cornyn said. “As recently as the last couple of days, they indicated they were likely willing to proceed based on the improvements to the underlying bill that they’ve been working on.”

Conservatives, meanwhile, lobbied for their concessions. Senate leaders agreed to include Cruz’s amendment in their revised plan, thereby allowing insurers to offer bare-bones health plans on the ACA market as long as they provide at least one option that meets the current law’s minimum requirements.

After McCain’s floor speech ended, most Senate Democrats headed down the stairs of the Capitol, where TV cameras were waiting for them. But even as they sought to rally with protesters, Republicans had put up an obstacle to their plans. Pence’s motorcade was speeding away, leaving the activists temporarily stranded on the other side of the street.