They joined Sens. Rand Paul (Ky.) and Susan Collins (Maine), who also oppose it. With just 52 seats, Republicans can afford to lose only two votes to pass their proposed rewrite of the Affordable Care Act. All 46 Democrats and two independents are expected to vote against it.
In a pair of tweets Tuesday morning, Trump decried the defections, called for letting the Affordable Care Act "fail" and vowed to keep pushing for a GOP plan.
"We were let down by all of the Democrats and a few Republicans. Most Republicans were loyal, terrific & worked really hard. We will return!" he wrote in the first tweet.
He followed that with: "As I have always said, let ObamaCare fail and then come together and do a great healthcare plan. Stay tuned!"
Republicans, who have made rallying cries against President Barack Obama's 2010 health-care law a pillar of the party's identity, may be forced to grapple with the law's shift from a perennial GOP target to an accepted, even popular, provider of services and funding in many states, which could make further repeal revivals difficult.
Meanwhile, Trump and other Republicans will confront a Republican base that, despite fervent support for the president, still seeks a smaller federal government and fewer regulations.
All of these forces remained vexing factors Monday as senators bailed on the bill. And no evident solution was offered by the White House — which has been limited in its sale of the GOP plan — or from McConnell, for how to bring together a party in which moderates and conservatives are still deeply divided over the scope of federal health-care funding and regulations.
McConnell did announce late Monday that he plans to push for a vote in the coming days anyway, but with a catch: senators would be voting to start debate on the unpopular House-passed bill. McConnell has promised to amend the bill to a pure repeal, but with no guarantee that such an amendment would pass.
"In addition to not repealing all of the Obamacare taxes, it doesn't go far enough in lowering premiums for middle class families; nor does it create enough free space from the most costly Obamacare regulations," Lee said in a statement.
Moran said the bill "fails to repeal the Affordable Care Act or address healthcare's rising costs."
The two senators timed the release of their statements and made clear that modest tinkering around the edges of the legislation drafted by McConnell would not be enough to meet their demands.
They joined a pair of GOP colleagues in calling for a complete redrawing of the legislation that would take many months, short-circuiting McConnell's wish to end the debate this month.
The news threw the effort to pass the legislation into turmoil, with additional Republicans weighing in on Twitter about a flawed process that must take a new direction. Trump tweeted that "Republicans should just REPEAL failing ObamaCare now & work on a new Healthcare Plan."
Sen. Lindsey O. Graham (S.C.) called for a "new approach" while Rep. Mark Meadows (N.C.) tweeted, "Time for full repeal." White House aides, meanwhile, said they still plan to press ahead.
The setbacks appear to have left McConnell and House Speaker Paul D. Ryan (R-Wis.) with few good options. Conservatives have suggested moving a bill that would simply repeal the Affordable Care Act and set up a timeline of several years to figure out how to replace it, a politically risky move that also might lack support to pass.
Another move, which McConnell threatened recently, would be to work with Democrats to prop up the insurance exchange markets that have been imploding in some states — which probably would win passage but would infuriate the conservative base that has been calling for the end of the Affordable Care Act.
"Regretfully, it is now apparent that the effort to repeal and immediately replace the failure of Obamacare will not be successful," McConnell said in a statement released late Monday. He revealed plans to move forward with a vote in the coming days anyway, in some ways daring his Republican opponents to begin debate and open the legislation up to amendments.
Democrats quickly jumped at the opportunity to declare the effort dead.
"This second failure of Trumpcare is proof positive that the core of this bill is unworkable," said Minority Leader Charles E. Schumer (N.Y.). "Rather than repeating the same failed, partisan process yet again, Republicans should start from scratch and work with Democrats on a bill that lowers premiums, provides long-term stability to the markets and improves our health-care system."
Republican leaders had returned to the Capitol on Monday still pledging to press ahead with plans to pass a far-reaching overhaul, but the day had begun with uncertainty as the health of Sen. John McCain put the future of the flagging effort deeper in doubt.
In a speech on the Senate floor, McConnell said that he had spoken with McCain (R) on Monday morning and that "he'll be back with us soon." The Arizonan is recovering from surgery to remove a blood clot above his left eye that involved opening his skull.
McConnell had delayed action on the health-care bill until McCain's return in hopes that he could be persuaded to vote yes. That hope faded after Lee's and Moran's announcements, however, with McCain issuing a statement from Arizona calling for a fresh, bipartisan start.
"One of the major problems with Obamacare was that it was written on a strict party-line basis and driven through Congress without a single Republican vote," McCain said. "As this law continues to crumble in Arizona and states across the country, we must not repeat the original mistakes that led to Obamacare's failure."
In addition, Sen. Ron Johnson (R-Wis.) hinted Monday that he might vote against advancing the measure to floor debate — departing from his posture last week.
McCain, 80, is awaiting results of tissue pathology reports "pending within the next several days," the hospital treating him said in a statement over the weekend. He will be away from the Senate for at least the rest of the week. A McCain spokeswoman had no further update on his condition Monday.
Graham, perhaps McCain's closest friend in the Senate, spoke to him by phone as he was walking to the Senate chamber for a vote Monday evening. The two had an animated conversation, and Graham said McCain was "dying to get back."
"They were doing a routine checkup and they found the spot and it looks like everything is going to be A-okay," Graham said. He said McCain's doctors "don't want him to fly for a week, adding, "I think he would walk back if they would let him."
The cause of McCain's blood clot remained unclear Monday. The most common causes of clots in the head, especially for older people, are falls, car crashes and other incidents that cause traumas, even minor ones, said Elliott Haut, a trauma surgeon at the Johns Hopkins University School of Medicine. By one estimate, 1.7 million people suffer traumatic head injuries each year, with motor vehicle accidents the leading cause and blood clots that affect the brain a common effect.
Traumas can cause blood to leak out of small vessels in two locations in the head: between the brain and a tough, fibrous layer known as the dura, causing "subdural hematomas," and between the dura and the skull, causing "epidural hematomas."
"People die of these every day," Haut said in an interview, emphasizing that he could not speak about McCain's health, because he had no details of the case.
Another possibility is that the clot is related to McCain's history of melanoma, a dangerous form of skin cancer that can spread to other organs, including the brain, and form new tumors. Haut said that is much less likely but not impossible. Diagnosis of a clot in the head requires a CT scan, and it often follows symptoms such as headaches or blurred or changed vision, he said.
Senate Republicans have been under self-imposed pressure to complete their work on health care. As they have struggled to show progress, McConnell has said he would keep the chamber in session through the first two weeks of August, postponing the start of the summer recess period to leave time to work on other matters.
Key Republican senators — and the GOP governors they turn to for guidance — have raised concerns about how the bill would affect the most vulnerable people in their states. Private lobbying by the White House and Senate GOP leaders has not mollified them.
Johnson said Monday that last week he was "strongly in favor" of taking a procedural vote allowing the bill to advance to floor debate. But he said he was unhappy with recent comments by McConnell that the bill's deepest Medicaid cuts are far into the future and are unlikely to take effect anyway.
Johnson said he read the comments in The Washington Post and confirmed them with other senators. He said he planned to talk to McConnell about it Tuesday at the weekly GOP policy lunch. In a statement late Monday, McConnell responded: "I prefer to speak for myself, and my view is that the Medicaid per capita cap with a responsible growth rate that is sustainable for taxpayers is the most important long-term reform in the bill. That is why it has been in each draft we have released."
New York Attorney General Eric Schneiderman, a Democrat, threatened Monday to sue the federal government if the health-care bill becomes law. The measure "isn't simply unconscionable and unjust. It's unconstitutional," he wrote on Twitter.
The Schumer letter also asks that GOP leaders not move ahead with the bill until the nonpartisan Congressional Budget Office releases a complete score on it. The CBO had been expected to release its findings as soon as Monday, but that did not happen. A GOP aide, who spoke on the condition of anonymity to discuss the matter candidly, said a release later this week was possible but not certain.
The CBO has been projecting what the bill would do to insurance coverage levels, premium costs and the federal budget deficit. Having an unfavorable report in the public domain for an extended period of time with an uncertain date for a vote would fuel critics' argument against the bill, making it harder for McConnell to round up votes for it.
A CBO report on an earlier version of the legislation projected that it would result in 22 million fewer Americans with insurance by 2026 than under current law. It predicted that the measure would reduce the budget deficit by $321 billion over the same period. On average, premiums would first rise, then fall under the measure, the CBO projected.
Neither a McConnell spokesman nor the CBO said when the new report would be released or why it was not released Monday.
White House officials have been seeking to cast doubt on the findings from the CBO and other independent analyses of the bill. But some key Republicans responded with skepticism.
Several key GOP senators have voiced concerns about the measure's long-term federal spending cuts to Medicaid. Others have said the bill would not go far enough in overhauling the Affordable Care Act. The opposing pressures have left McConnell in a tough position in which he has struggled to find a solution.
In the meantime, Senate Republican leaders plan to focus on trying to confirm more Trump administration nominees and some less far-reaching legislative goals. As they do, they will be watching for updates on McCain's condition.
"Following a routine annual physical," the Mayo Clinic Hospital in Phoenix said Saturday, McCain "underwent a procedure to remove a blood clot from above his left eye on Friday, July 14." The hospital added that "surgeons successfully removed the 5-cm blood clot during a minimally invasive craniotomy with an eyebrow incision."
Acute subdural hematomas can be fatal half the time and even more often in older people. They can also cause strokes. Unlike clots in the legs and lungs, they must be treated through surgery, rather than blood thinners, Haut said.
Evan Wyloge in Phoenix and Paul Kane, Robert Costa, Kelsey Snell, Abby Phillip and William Branigin in Washington contributed to this report.