Senate Majority Leader Mitch McConnell (R-Ky.) plans to put a bill written by Sens. Lindsey Graham (R-S.C.) and Bill Cassidy (R-La.) to a vote, hoping that a looming Sept. 30 deadline to pass the bill with just 50 votes will create enough pressure to finally pass a repeal of the health care law, his office said.

“It is the leader’s intention to consider Graham/Cassidy on the floor next week,” a spokeswoman said.

McConnell has told colleagues he will only bring up the bill if it will succeed. The statement does leave some wiggle room to not proceed with a vote.

It’s still anyone’s guess whether the bill’s backers can get to 50 votes. One Republican senator suggested that McConnell may ultimately decide to bring the bill up for another failed vote, in part to show GOP donors and President Donald Trump that the Senate GOP tried again.

Trump himself joined the ongoing debate Wednesday night, tweeting that Graham-Cassidy was a “great Bill.”

“I would not sign Graham-Cassidy if it did not include coverage of pre-existing conditions. It does!” Trump tweeted, alluding to recent attacks on the bill that it won’t protect patients with congenital or pre-existing illnesses.

Sens. Rand Paul (R-Ky.) and Susan Collins (R-Maine) are viewed as hard “no’s.” And Sens. John McCain (R-Ariz.) and Lisa Murkowski (R-Alaska), who opposed a previous iteration of repeal in July, are not sold on the proposal.

In an interview, McCain sounded like he could end up tanking a bill written by Graham, his close friend.

“Nothing has changed. If McConnell wants to put it on the floor, that’s up to McConnell,” McCain said. “I am the same as I was before. I want the regular order.”

Asked if that means he’s a “no” vote, McCain said: “That means I want the regular order. It means I want the regular order!”

Paul, who has come under criticism from fellow Republican senators and Trump himself for his adamant opposition to the Graham-Cassidy measure, showed no sign of backing off Wednesday. In an interview, the Kentucky senator said he plans to demand a vote next week — should the bill actually come to the floor — on an amendment that would simply repeal the entirety of the health care law.

That amendment would go further than a vote Paul secured in July that repealed the main pillars of Obamacare, including the coverage mandates and the Medicaid expansion.

“My objection is that it keeps the vast majority of Obamacare spending and then just redistributes it in a different formula. That, to me, isn’t what I promised,” Paul said. “I’m going to have a vote on repealing the whole thing and we’ll see how people stand on that.”

Murkowski said Wednesday that she is still undecided, stressing that she needs “full understanding as to numbers and formulas” under the Graham-Cassidy bill.

“Just last evening, late, my team was on the phone with the folks from [Health and Human Services] because we’ve got hard questions about numbers that we feel that we deserve an answer to,” Murkowski said. “So we’ve been working through that.”

The latest proposal would turn federal health insurance funding into block grants for states, wind down Obamacare’s Medicaid expansion and rescind the law’s coverage mandates. Notably, there will be no complete analysis by the Congressional Budget Office by the time a vote comes up, leaving lawmakers unsure what the bill’s effects on premiums and coverage will be.

That’s been a major critique from Senate Democrats, who are again chastising Republicans not only for the substance of the Graham-Cassidy bill but how Republicans are scrambling to pass it before Sept. 30. Senate Minority Whip Dick Durbin of Illinois said Wednesday that “we’re going to do everything we can to make it clear how bad this bill is, offer the appropriate amendments and hope that three Republicans will join us in stopping it.”

The uncertainty surrounding the last-ditch repeal push has kept many center-right senators on the sidelines, including McCain, Murkowski and Sens. Rob Portman (R-Ohio) and Shelley Moore Capito (R-W.Va.). However, at a party lunch on Tuesday before leaving for the week, the vast majority of senators expressed support for holding a vote on the bill, according to an attendee.

The party’s chief vote-counter, Majority Whip John Cornyn of Texas, said party leaders are delivering an urgent message to wavering Republicans.

“It really seems to be picking up some momentum. And I think it’s happening pretty quickly,” Cornyn said in an interview. “We don’t have long to act so that’s why things seem to have sprung up here after people thought health care was dead. This is our last opportunity.”

Cassidy and Graham have been working feverishly to educate senators about the bill, working with CBO to get them the most information possible, a source familiar with the process said. The duo, along with former Sen. Rick Santorum (R-Pa.), spent Wednesday morning meeting with McConnell and working on Murkowski and Sen. Dan Sullivan (R-Alaska), hoping to overcome their concerns that block grants could slash funding to Alaska.

“We’re very interested in helping Alaska because Alaska has 750,000 people. And a land mass bigger than Texas,” Graham said, referring to a provision in the bill that could help low-density states such as Alaska.

Most of the whipping will focus on McCain and Murkowski. Both took an immense political risk in rejecting the GOP’s “skinny” repeal in July, and Republican senators believe that if the two of them support the bill, the rest of the undecided Republicans will fall in line.

“It’s going well,” Cassidy said of the discussions with McCain and Murkowski. “I don’t want to say in play … but they are open to these discussions.”