It was one of his most explicit acknowledgments that his party's top-priority drive to erase much of Obama's landmark 2010 statutes might fall short.
The remarks by McConnell, R-Ky., also implicitly meant that to show progress on health care, Republicans controlling the White House and Congress might have to negotiate with Democrats. While the current, wide-ranging GOP health care bill - which McConnell is still hoping to push through the Senate - has procedural protections against a Democratic Senate filibuster, a subsequent, narrower measure wouldn't and would take 60 votes to pass.
The existing bill would fail if just three of the 52 Republicans vote no, since all Democrats oppose it. McConnell was forced to cancel a planned vote on the measure last week after far more Republicans than that objected, and he's been spending the Independence Day recess studying possible changes that might win over GOP dissidents.
"If my side is unable to agree on an adequate replacement, then some kind of action with regard to the private health insurance market must occur," McConnell said at a Rotary Club lunch in this deep-red rural area of southern Kentucky. He made the comment after being asked if he envisioned needing bipartisan cooperation to replace Obama's law.
"No action is not an alternative," McConnell said. "We've got the insurance markets imploding all over the country, including in this state."
In a written statement, Senate Minority Leader Chuck Schumer, D-N.Y., called it encouraging that McConnell had "opened the door to bipartisan solutions." He said the focus should be on continuing federal payments to insurers that help them contain costs for some low-earning customers. Trump has threatened to end these payments.
Schumer has repeatedly said Democrats won't negotiate until Republicans abandon their repeal effort.
McConnell's comments came during a recess that has produced no visible evidence that he's winnowed the number of unhappy Republican senators. If anything, the list seemed to grow this week as Sen. John Hoeven, R-N.D., said he opposed the bill, but he was vague about changes he'd want.
That brought to at least a dozen the GOP senators who've publicly opposed or criticized the legislation, though many are expected to be won over by revisions McConnell is concocting.
Even as Republicans have struggled to write legislation they can pass, some have acknowledged that if they encountered problems, a smaller bill with quicker help for insurers and consumers might be needed. They've said it could include provisions continuing the federal payments to insurers, which total around $7 billion annually, and some inducements to keep healthy people buying policies - a step that helps curb premiums.
Trump, McConnell, House Speaker Paul Ryan, R-Wis., and other Republicans have said Obama's law is failing, citing markets around the country where insurers have pulled out or sharply boosted premiums. Some areas are down to a single insurer.
Democrats acknowledge Obama's law needs changes that would help curb the growth of health care costs. But they say the GOP is exaggerating the problem and note that several insurers have attributed their decisions to stop selling policies in unprofitable areas, in part, to Trump administration indications that it may halt payments to insurers. A federal court has ruled the payments weren't authorized by Congress but has allowed them to temporarily continue.
In its report last week on the Senate bill, the nonpartisan Congressional Budget Office said that under Obama's law, it expected health care markets "to be stable in most areas."
It said the same about the Senate legislation. But it also said under the GOP bill, 22 million added Americans would be uninsured because it would eliminate Obama's tax penalty on people who don't buy coverage and it would cut Medicaid, the health insurance program for the poor, disabled and many nursing home patients.
McConnell spoke hours after Sen. Ted Cruz, R-Texas, said the bill's prospects were "precarious." Speaking on San Antonio's KTSA Radio, Cruz said the GOP's Senate majority "is so narrow, I don't know if we can get it done or not."
Further qualms were voiced by Sen. Jerry Moran, R-Kan.
"There are people who tell me they are better off" under Obama's law, "and I believe them," Moran said at a town hall meeting Thursday in Palco, Kansas. Moran, who'd said he could not support the current version of the bill, said health care is "almost impossible to solve" with the slim GOP majority in the Senate.
McConnell said he expected to have a new version of the legislation ready in "a week or so." Another Republican, Sen. Pat Toomey of Pennsylvania, suggested it may take some time before McConnell can win enough support.
"We're still several weeks away from a vote, I think," Toomey said Wednesday while appearing before a live studio audience at WHTM-TV in Harrisburg, Pennsylvania.
Toomey partly attributed some of the GOP's problems to Trump's surprise victory last November.
"I didn't expect Donald Trump to win, I think most of my colleagues didn't, so we didn't expect to be in this situation," he said.
AP reporter Marc Levy contributed from Harrisburg, John Hanna from Palco and Fram from Washington.
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