A reminder: Senate Republicans can afford to lose Sen. Bob Corker and one more, and if there's perfect attendance, still pass the bill with the assistance of Vice President Mike Pence casting the 50-50-tie-breaking vote. It remains to be seen if new problems arise in the next 24 hours, but early indications are the conference should stick close to its original votes with the new deal.
Here's the latest on what the key senators are saying about how they'll vote.
"I've been pretty consistent in my communications on this issue and that is I want us to see the refundable portion of the child tax credit increased from its current number," Rubio told reporters on Capitol Hill on Thursday. "If it stays at $1,100, I'm a 'no.' Let's hope it doesn't."
Despite the very real revenue issues Republicans face on their tax bill, Senate GOP leaders are working to put more money toward the refundability piece of the child tax credit, according to two GOP sources involved in the process. The amount is currently being negotiated and it's unclear Rubio will get exactly what he wants, but he will get something, the sources said.
Sen. Bob Corker
Corker, a Tennessee Republican who's not seeking re-election, was the sole GOP senator to vote against the tax legislation on its initial passage through the chamber and there's little reason to believe that he would change his mind this time around.
An aide to Corker told CNN on Thursday that Corker wants to examine the final agreement before deciding how he will vote.
Corker told CNN on Wednesday, "I have all the same concerns that I have had," which are focused on the impact of the bill on the deficit. He remains in conversations with Trump administration economic officials about the bill.
Sen. Jeff Flake
Like Bob Corker, Sen. Jeff Flake is not seeking re-election and was critical of the tax bill's affect on the deficit. Unlike Corker, Flake ultimately voted to advance the legislation out of the Senate.
On Thursday, Flake told CNN that he's still looking at the tax bill and hasn't made a decision on how he will vote.
Flake make clear his support was contingent on a slower phase out of the expensing provision in the Senate legislation. It's still unclear how the conference deal treats that provision -- making Flake's support still unknown at this point.
Sen. Susan Collins
Sen. Susan Collins of Maine is still evaluating the proposal, but made clear Wednesday slowing down the process wasn't necessary. She hasn't wavered on what she needs -- the provisions she got to vote "yes" on the Senate proposal, plus separate health care items. GOP leaders are working to make those things happen.
Sen. John McCain
McCain, who announced he had brain cancer this summer, was hospitalized this week "for normal side effects of his ongoing cancer therapy," his office said in a statement Wednesday night.
"Senator McCain looks forward to returning to work as soon as possible," the statement said, though it did not include any details on the timing of his return.
Flake said Thursday he spoke to McCain's wife Cindy McCain on Wednesday night about Sen. John McCain's health.
"We expect him back," Flake said. "I expect him back. He's obviously recovering from the effects of the treatment and so we expect him back."
Sen. Thad Cochran
Sen. Thad Cochran of Mississippi had "an outpatient procedure Monday afternoon to address a non-Melanoma lesion on his nose," his spokesman Chris Gallegos told CNN. "The procedure was more extensive than expected, but the senator is doing well and available now for votes if needed."
"Senator Cochran is in Washington and expects to vote for the tax plan when it comes to the Senate next week," Gallegos added.
Cochran has had health issues throughout the fall, including a urinary tract infection that kept him out of office for several weeks in October. At the time, Cochran said he thought he was physically fit for office.
This is a delicate situation for GOP leaders, but the expectation is Cochran and McCain will be back for any votes next week.