Senate Republicans will not vote on a bill to repeal and replace Obamacare this week, extinguishing the chances of passing the measure by a Sept. 30 deadline that would have allowed the GOP to avert a filibuster by the Democrats.

Majority Leader Mitch McConnell, R-Ky., pulled the plug on the effort a day after a third Republican came out against the legislation, authored by Sens. Lindsey Graham, R-S.C., and Bill Cassidy, R-La., which would have replaced Obamacare funding with a block grant system that would have let states control both the fate and funding of the embattled healthcare law.

"We don't have the votes," Cassidy said after Republicans emerged from their meeting.

"We made the decision because we don't have the vote, we'll postpone the vote," said Cassidy, a physician who added that he is "disappointed."

An upbeat Graham said after the meeting they are going to try to move the bill again next year.

"We are coming back to this after taxes," Graham said, referring to the tax reform legislation that Congress hopes to complete by the end of the year. "We are going to have time to explain our concept. We'll have a better process and we are going to take this show on the road."

Sen. Susan Collins, R-Maine, said Monday she will not vote for the bill, leaving the GOP at least one vote shy of the minimum 50 Republicans they would need to pass the legislation. With just 50 votes, Vice President Mike Pence would have cast the tie-breaking vote.

Sens. John McCain, R-Ariz., and Rand Paul, R-Ky., also pledged their opposition.

Lawmakers have not abandoned their desire to try to pass a healthcare bill, and are now examining whether language might be included in an upcoming tax reform bill that is the only remaining legislative vehicle immune to a filibuster by Democrats.

McConnell said the next step for Republicans would be to tackle tax reform.