The Senate is poised to vote on a budget resolution later this week, the first in a two-step process of rolling back major parts of the Affordable Care Act. At the same time, GOP lawmakers are speaking out with force, concerned about the political backlash if the GOP is perceived as being reckless given that 20 million Americans have health coverage through Obamacare and there's no clear vision or firm timeline for an alternative.
These early concerns indicate swelling reservations over what's become known as the GOP's "repeal and delay" strategy -- voting on repeal but delaying the repeal from going into effect for several years, buying the party time to craft a replacement plan.
Sen. Bob Corker warned fellow Republicans that it would be "problematic," "not very appealing" and "doesn't seem very intelligent" to repeal the law without a replacement.
"To me, it's much more prudent to figure out where you're going to go from here, and attempt to do it all at the same time," the Tennessee Republican told CNN. "People will see some of the flaws in just repealing only."
Sen. Rand Paul is emerging as one of the most vocal GOP opponents of voting on a repeal bill before coming up with a replacement package, as he argues that the two votes must happen simultaneously.
"I will do everything in my power to have a vote on it the day we repeal Obamacare," Paul told CNN's Wolf Blitzer on Monday, noting that Trump personally expressed his support for this approach in a phone call with the senator.
The Kentucky senator is planning to unveil replacement legislation in the coming days. His spokesman separately told CNN that Paul plans to vote against the budget resolution this week over budgetary reasons, and wouldn't say whether Paul could vote against a reconciliation bill later this year that would carry the repeal language.
'I want to see the game plan'
Republicans are using a fast-track budget mechanism to repeal major portions of Obamacare in order get around a Democratic filibuster in the Senate.
But they are keenly aware that passing any replacement package or series of smaller bills afterwards will require 60 votes in the Senate -- in other words, some Democratic support.
Wisconsin Sen. Ron Johnson told CNN Monday: "I want to see the game plan in terms of how you actually enact replacement."
"I take (Senate Minority Leader Chuck) Schumer at his word that if we just go ahead and repeal, Democrats won't provide one vote for enacting the replacement," he said. "So I think we need to actually have a game plan."
Asked whether he might vote against the reconciliation bill that repeals Obamacare if there isn't a replacement plan by the time Congress takes it up, Johnson simply said: "That's hypothetical. I'm hoping we'll have one."
Sen. John McCain, who previously suggested he would like his party to slow down on repeal efforts, demurred when asked Monday if he had concerns about a "repeal and delay" strategy.
The Arizona senator said he "can't describe exactly how" the process would unfold, before settling on a simple declarative statement: "We will replace."
Planned Parenthood politics
One other potential sticking point is Planned Parenthood.
House Speaker Paul Ryan last week announced that the party intends to use the budget reconciliation bill to strip all federal funding for the group. At least two pro-choice senators -- Sens. Susan Collins of Maine and Lisa Murkowski of Alaska -- have not committed to approving an Obamacare repeal bill
if it includes a measure to defund Planned Parenthood.
Losing the support of this pair of GOP senators could be detrimental to the party's repeal efforts.
Murkowski told CNN on Monday that she doesn't have reservations about voting for the budget resolution this week, but that the party must "figure out what everything looks like later on."
"We are going to have plenty of time for lots of good conversations," the senator said when asked whether she has spoken with Senate leadership about her concerns.
What this week -- and beyond -- will look like
Senate leadership aides expect the chamber to vote on the budget resolution around Thursday.
Once the resolution has been approved in the Senate, the House is expected to take it up right away -- possibly as early as Friday. A House GOP source said they expect the proceedings to approve the budget resolution in the House to be "straightforward."
At this point, a number of congressional committees will start crafting a budget reconciliation bill -- legislation that that would repeal major parts of the Affordable Care Act.
This bill would only require a simple majority in the Senate for passage, allowing Republicans to avoid a Democratic filibuster. Under pressure to make faster progress on a replacement plan, Senate Republicans are now exploring ways to fold in some "replace" measures
into this repeal bill.
It could be weeks -- possibly even months -- before the House and Senate vote on the legislation and send it to future-President Donald Trump to sign.
Congress will then turn to the much more complicated task of replacing what they voted to roll back. Any replacement bill will need 60 votes in the Senate, which means Republicans will need to pick up support from at least eight Senate Democrats -- a tall order in the current partisan climate but possible through lengthy negotiations and compromise.
Some moderate Democrats, including West Virginia Sen. Joe Manchin, have indicated that they are willing to work with colleagues across the aisle.
GOP leaders have recently started to suggest that they want to pass incremental replacement bills rather than one comprehensive bill, calculating that it will be easier to garner bipartisan support for smaller replacement bills.
"We're not going to do a comprehensive bill. We are going to do it in a step-by-step basis," Cornyn said last week.