The Affordable Care Act (ACA) survived another review at the Supreme Court on Thursday. But Obamacare isn’t out of the woods yet. There will be a new president in January 2017, and if that president has a tall “R” next to his or her name, the pressure to undermine the ACA will be high. Republicans wouldn’t have any great options. But here are several things they might try, in order of least to most likely to happen.

Full repeal

To make good on the GOP mantra of “repeal and replace,” Republicans would have to hold Congress, then do what they’ve been unable to do since 2009 — unite behind an alternative health-care proposal. There is at least one real GOP replacement plan on the table, from Sens. Richard Burr (N.C.), Tom Coburn (Okla.) and Orrin Hatch (Utah), but it probably wouldn’t attract enough support among hard-right conservatives. Even if Republicans coalesced around a replacement plan, Senate Majority Leader Mitch McConnell (R-Ky.) would have to find a procedural way around an inevitable Democratic filibuster. That could conceivably involve ending the filibuster altogether, a move that former Senate majority leader Harry Reid teed up when he ended the filibuster on presidential nominees in 2013.

In other words, a lot of things would have to go right for the GOP to pull off a full repeal and replace.

Partial repeal

There are many things Republicans could do short of a full repeal that would nevertheless undermine the law. Electing a GOP president and a GOP Congress next year would almost guarantee the death of Obamacare’s medical device tax, a source of revenue for the health-care expansion that Republicans may or may not make up with something else. Cutting the tax would represent raw interest group pandering, but conservatives would be attracted to anything that’s hostile to Obamacare, and losing the revenue could bolster GOP claims that the policy is unaffordable.

It’s also likely Republicans would push to relax insurance coverage requirements, allowing people to buy skimpier plans. Though some people would end up paying less, they would also get less protection. ACA backers argue that the least generous health-care plans currently allowed are already pretty basic. Moreover, any tinkering with what people have to pay into the system would risk throwing it out of financial balance. But these considerations still might not stop Republicans committed to rollback, and this sort of change might not seem as threatening to Democrats seeking to protect the law.

Meanwhile, rolling back the ACA’s individual mandate, which requires people to carry health-care insurance, seems to be a mainstream GOP position, even though it would send insurance markets spiraling. Unless Republicans want to be blamed for a policy disaster, they would have to replace the mandate with some other incentive for people to buy insurance or pass a much broader Obamacare replacement package. Either would probably be easier than passing a comprehensive replacement plan, but not by much.

In other words, any ambitious legislative change to the ACA would have to account for Democratic opposition and the predicted 24 million people the law will cover by 2017, both of which would leave GOP lawmakers with some, but not ample, room to maneuver.

Presidential action

Remember when Mitt Romney promised to issue Obamacare “waivers” to every state on his first day in office? The ACA gives the executive branch a fair amount of leeway in implementing pieces of the law, and a Republican president could rely on these authorities to undercut the policy. Timothy Jost, a Washington and Lee law professor and ACA specialist, maps out several paths. Formal rules that the Department of Health and Human Services or other agencies have already established could be redrawn, though that would invite legal challenges. Yet, Jost wrote in an e-mail, “a great deal of the ACA implementation has been through informal guidance, and this could be more easily revised.” Also, “a future administration could delay implementation of various requirements, as has the current administration, perhaps indefinitely.”

Finally, “perhaps the easiest thing for a president hostile to the ACA to do would be to liberally grant 1332 waivers to the states,” Jost wrote. 1332 waivers exempt states from many ACA requirements, allowing them to experiment with health-care policy models, as long as those experiments result in affordable coverage options, cover a comparable number of people as standard Obamacare would have and don’t add to the debt. These stipulations seem to limit the opportunity for mischief. But the affordability and comparability requirements could both be interpreted loosely. A GOP Congress could also ease these restrictions, conceivably allowing conservative states to hack away at Obamacare on their own.

Now that the Supreme Court has ruled, the ACA is on sure footing for the next year and a half, and it is unlikely that it will go away after that. Republicans will try to please the base as best they can, and they could do some damage. But their hardest task might be placating conservatives who demand a spectacular policy reversal.