By MARY ELLEN McINTIRE and JOE WILLIAMS

Abrupt news that Arizona Sen. John McCain was diagnosed with brain cancer sent shock waves through an all-Republican meeting late Wednesday on the health care effort. Amid words of concern and encouragement for their GOP colleague, lawmakers acknowledged the difficulty his extended absence would place on the effort to overhaul the U.S. health insurance system.

Initial reports of McCain’s July 14 surgery for a blood clot led Senate Majority Leader Mitch McConnell to postpone a procedural vote initially planned for this week.

McConnell needs to secure the backing of 50 of the Senate’s 52 Republicans to pursue his strategy of moving a Senate version of the House-passed health care bill through the special budget reconciliation process. McCain’s continued absence likely raises the stakes for McConnell if he sticks with his plan for a vote next week.

“Obviously, I think more people are worried about his health than thinking about the math, but you know, you understand the math,” Tennessee GOP Sen. Bob Corker told reporters about McCain. “Obviously, it makes things difficult.”

McCain’s Absence Leaves Health Care Bill Stalled

The more than two-hour meeting late Wednesday night comes a day after McConnell proclaimed there was not enough Republican support to advance a bill to repeal and replace the 2010 health care law. The legislation’s collapse is a blow to the party’s seven-year effort to gut President Barack Obama’s signature domestic achievement.

Senators, however, remain optimistic a compromise can be reached and have been working behind the scenes to try to come to consensus.

Lawmakers such as Sens. Lisa Murkowski of Alaska, John Hoeven of North Dakota, Bill Cassidy of Louisiana and Patrick J. Toomey of Pennsylvania huddled in the office of Republican Policy Committee Chairman John Barrasso of Wyoming to discuss policy issues, but largely avoiding any talk of strategy or timing.

“I feel positive about it. Some old ideas were discussed, some new ideas were discussed. I think we’ve made a lot of progress. Everybody’s mindful of the deadline,” Sen. John Kennedy of Louisiana said after the Republicans’ Wednesday meeting.

Kennedy said everyone in the meeting was operating in “good faith,” but major questions remain over how the Senate will move forward.

Murkowski, a key swing vote, said it remained unclear what exactly the Senate would consider next week if enough members vote to clear the procedural hurdle.

“There’s nothing really new in terms of new challenges,” South Dakota Sen. Michael Rounds said after the meeting. “They’re the same challenges that we faced before, it’s just a matter now of finding the plans to work them through.”

Senate aides were kicked out midway through the meeting — a move that lawmakers said was done so they could talk among themselves — as reporters were regulated to a specified portion of the hallway of the Dirksen Senate Office Building.

“We’re at our best when we’re among ourselves. That’s just human nature,” Kennedy said.

Even if Republicans cannot find the 50 votes needed to advance a repeal and replace plan, it is expected that McConnell will still hold a vote — if the initial vote on the motion to proceed is successful — on a measure passed by Congress in 2015 that would repeal large portions of the law. There would be a two-year delay in implementation.

The nonpartisan Congressional Budget Office said earlier Wednesday that the measure could increase the amount of uninsured people by 32 million, beyond the current trajectory, over the next 10 years. It could also significantly raise premiums and cause insurers to largely abandon the individual market.

The night was not without fireworks.

A small group of protesters stood outside the door, chanting “Kill the bill, don’t kill us” until they were ushered out by Capitol security once the building closed.

Lauren Clason contributed to this report.