(CNN) Republicans are moving at lightning speed to repeal Obamacare.
After that, everything is an open question -- and a potential political nightmare.
Not only does the GOP lack a replacement plan, there is no consensus on how long it will take Republicans to come up with and pass a comprehensive health care bill -- or a series of smaller measures -- or how many people would have health insurance under it.
House Speaker Paul Ryan said Thursday that Congress will act this year, but didn't issue a firm deadline or say what the law will look like.
"Our legislating will occur this year. Our legislating on Obamacare, our repealing and replacing and transitioning -- you know, the legislating will occur this year," Ryan told reporters.
Ryan also won't specify who would be covered under a new GOP system. Pressed whether the same amount of people covered currently would be covered under a new system, the speaker punted, saying he didn't want to get ahead of committee action.
Senate Majority Whip John Cornyn of Texas said Thursday Republicans wouldn't even offer a comprehensive bill to replace Obamacare, opting for individual health care measures instead that could draw bipartisan support.
The worry: a full-scale bill will become unwieldy and will be difficult to attract support.
"We're not going to do a comprehensive bill. We are going to do it in a step-by-step basis," Cornyn, the No. 2 Senate Republican, told CNN. "If I've learned anything since I've been here in the Senate, big comprehensive bills are not the way to go."
Adding factors such as defunding Planned Parenthood, which Ryan pledged to do Thursday, could also make things more difficult for the GOP.
No matter what, the clock is ticking for Republicans.
Following a House GOP conference meeting Wednesday featuring Vice President-elect Mike Pence, Rep. Chris Collins said the party was looking at a half-year window in which to come up with a replacement.
"I think six months is a date we have talked about within our conference," said Collins, who serves on President-elect Donald Trump's transition team. "Within six months, we should be able to put pen to paper and have a replacement plan. Certainly we're not doing that on day one."
But a Ryan aide said there's no such deadline and that one wasn't discussed in the gathering with Pence.
"Our goal is to provide relief from this terrible law as soon as possible and we have not detailed a hard deadline," a Ryan aide told CNN Thursday morning. "Our goal is as soon as possible."
Not everyone in the House GOP conference is on board with Ryan's "soon as possible" approach. Colorado GOP Rep. Mike Coffman said Wednesday that a six-month timeline for presenting a replacement plan is "awfully short."
"If it is too short there's a concern that the insurance market can't price for that," Coffman said.
The internal frictions that has started to emerge within the GOP is emblematic of the party's broader political dilemma on Obamacare.
For Obamacare's inception in 2010, Republicans have railed against the President's signature health care reform law and vowed to roll it back. Now, just days away from controlling the House, the Senate and the White House, Republicans are eager to please their base by delivering instant Obamacare repeal.
But this political move comes with numerous policy and real world consequences -- health care experts, insurance companies and Americans who have coverage through Obamacare have begun to ring the alarm bell.
This reality that has made it difficult for the GOP to quickly present details and deadlines on Obamacare replacement.
To calm fears of potential chaos, GOP leaders are promising a "transition" period as part of a "repeal and delay" plan. But there is also no consensus on how long Republicans want to delay the repeal from going into effect.
Ryan said questions about when a replacement program would begin working -- assuming one is passed -- are open for discussion.
"What date all of this gets phased in on is something we do not now know, because we're waiting for the Trump administration to be stood up," Ryan said. "We're waiting for Tom Price to be confirmed and become the secretary of Health and Human Services. The question there is, how long will it take for markets to put in place, for markets to adjust. That question we don't know the answer to, but the legislating on Obamacare will happen this year."
Democrats are pressuring Republicans on their plan to move forward with repealing Obamacare without having a replacement in sight.
In a speech on the Senate floor Thursday, Senate Minority Leader Chuck Schumer again accused Republicans for playing a "game" with health care without having a plan on how to move forward.
"It's no longer just a game or a political line to say 'repeal.' Because now, you have to replace," Schumer said. "So far, it's been five years of repeal, repeal, repeal. Not one replace plan has garnered a lot of support even on the Republican side of the aisle let alone in America."
Ryan called such statements "scare tactics."
"I think they're trying to make Americans think like someday this February or someday this March you're going to wake up and you won't have a health insurance plan. That ain't happening. That's not true," Ryan said. "What we're doing is we're going to be methodical, we're going to be deliberative, and we're going to do this the right way. We're going to get this law repealed. We're going to get this law replaced. And we're going to have a transition period so that people do not have the rug pulled out from underneath them while we get to a better place."