That’s not the GOP’s only problem. Under those rules any Obamacare repeal has to reduce — not increase — the deficit. So Republicans will have to pick and choose which parts of the Affordable Care Act they most want to ditch.

Obama will, of course, veto any bill that significantly damages his signature domestic policy achievement. But the entire process has the makings of a difficult political exercise that will reveal something about the GOP’s priorities when it comes to the reviled law, forcing the party to go beyond the pile-on repeal rhetoric and say specifically what it would do and how it would pay for it.

Republicans could try to get rid of the mandates and taxes, but then they’d have to plug a trillion-dollar hole. Cut the Medicaid expansion to the states? Sounds simple enough, but then they could put themselves at odds with governors.

They’ll also have to decide if they want to scrap federal Obamacare subsidies, currently on the hot seat across the street at the Supreme Court, which this month will rule whether they’re constitutional. Gutting them would yield almost a trillion dollars in savings, which could then be used to repeal other parts of the law. But moderates also may experience a political backlash for slashing health care tax credits for poor and middle-class families. Extending or replacing the subsidies, though, could further limit their repeal options and alienate conservatives at the same time.