Senate Republicans are struggling to pass their latest healthcare overhaul — a bill written by Sen. Lindsey Graham (R-S.C.) and Sen. Bill Cassidy (R-La.) — by a Sept. 30 deadline.
But it's not clear they will have the votes, meaning GOP leaders and President Trump may fail again to repeal the Affordable Care Act, also known as Obamacare.
Here's a look at why Republicans are rushing to pass a bill and what's next if they fail.
If this fails, does that mean the Republican effort to end ACA is over?
Not likely. Republicans have promised for seven years to undo Obamacare and their voters expect them to deliver. Bipartisan efforts to improve the Affordable Care Act had been underway, and those may likely resume if this week's vote fails.
But there will almost surely be pressure on Republicans to keep trying to pass their own bill to repeal and replace the healthcare law.
"Eventually we'll win," Trump told reporters over the weekend, "whether it's now or later."
Why are Republicans rushing to finish before Sept. 30?
The Senate is relying on special budget rules that would allow passage of the healthcare bill with a simple majority, bypassing the threat of a filibuster by opponents.
So-called budget reconciliation provides a potentially powerful strategic advantage for Republicans. They hold a slim 52-seat majority and would almost certainly be unable to reach the 60-vote threshold needed to overcome a filibuster by Democrats or even Republican opponents of the bill. Using the budget process, Republicans need only 50 votes, assuming Vice President Mike Pence casts the tie-breaking vote.
But budget rules, which need to be approved each year, are set to expire on Sept. 30, at the end of fiscal 2017.
Some believe the Senate could vote to change the deadline, but so far most seem to be accepting the Sept. 30 date.
Won’t there be another budget? Can't they use that same budget reconciliation process again?
Yes. Republicans could approve a new budget for fiscal 2018 with similar reconciliation instructions on healthcare.
"We're not going to vote for a budget resolution that doesn't allow the healthcare debate to continue," Graham said Sunday on ABC.
But passing budgets has proven difficult for Republicans, even though they have the majority in the House and Senate. The party is split between strict deficit hawks and those willing to spend more on defense and other items.
Moreover, Republicans have been planning to use the 2018 budget reconciliation for tax reform, so that it, too, can be approved without a filibuster threat in the Senate. It would be difficult to do both tax reform and healthcare in the same reconciliation process.
So will there definitely be a vote this week on the Graham-Cassidy bill?
It's looking less and less likely.
Last week, Senate Majority Leader Mitch McConnell said a vote would be held this week, and over the weekend White House officials said they expected one on Wednesday.
But Monday, amid dimming prospects, McConnell would not commit to a vote. He is not likely to want to endure another embarrassing failure on the Senate floor, so he may not call a vote unless he's sure he has the support. That's unlikely with three Republicans now opposed to the bill.
What are the chances of passing a healthcare bill with 60 votes?
Republicans would need to win over at least eight Democrats in the Senate, maybe more, to reach the 60 votes needed to overcome a filibuster.
Democrats want to work on improvements to Obamacare, and had been working on bipartisan fixes in the Health committee. But they have shown little interest in providing votes unless Republicans drop their repeal-and-replace framework.
If Republicans continue to go it alone, chances for passage remain slim.
What are the chances of the bipartisan compromise?
Better, but far from certain.
After the last collapse of the GOP repeal effort, Sens. Lamar Alexander (R-Tenn) and Patty Murray (D-Wash.) began working on a compromise to stabilize insurance markets and fix problems with the current law.
But once the Graham-Cassidy bill began to gain momentum a week ago, Alexander abruptly announced that effort had failed. Many viewed his statement as an attempt to narrow the options for Republicans and drive support toward the Graham-Cassidy bill. Murray insisted Democrats were still interested in working toward a compromise.
If Graham-Cassidy fails, there may be more interest in reviving the bipartisan effort, which many healthcare groups have advocated.
3:15 p.m.: This article was updated with more information about the bipartisan effort.