There’s this game in American politics where folks who fancy themselves conservative often condemn programs that they in fact want very much. Obamacare is one such example.

We face a possible moment of truth in a case now before the U.S. Supreme Court. If the justices rule a certain way, Americans in the 36 states covered by the federal exchanges would lose their federal subsidies.

Gone would be guaranteed coverage for those with pre-existing conditions. Gone would be affordable premiums for families buying their own insurance. Millions would be thrust back into the health care wilderness.

The health coverage promised under the Affordable Care Act is under threat — but not for those whose governors established state-run exchanges. The great majority of Republican governors did not, framing their decision as principled opposition to Obamacare.

And they could safely voice their defiance because Democrats wrote the health reforms to include subsidies for their people through the federal exchanges. Their electorates would not be amused at losing that coverage.

Forget about those polls showing widespread dislike of Obamacare. The law is complex, and the flood of anti-Obamacare propaganda sows constant confusion. But one reality has been seeping in: The health reforms protect Americans against financial ruin in a medical crisis.

Look instead at how many politicians condemned the program but how few recently ran for election saying they’d repeal it. And though anecdotal, stories are legion of Americans denouncing Obamacare as they sign up for their subsidized coverage.

This disconnect poses a problem for Republicans with presidential ambitions. On the way to the nomination, they must please an older conservative base unalterably hostile to a government-run health plan — except the one covering them. (You wonder at those who would deny guaranteed health coverage to working families but not touch a hair on their Medicare.)

This puts New Jersey Gov. Chris Christie in a tough spot. He did not set up an exchange in his generally liberal state, many believe, to appease the right-wingers standing in the way of a presidential nomination. That didn’t matter greatly, because the voters at home had a federal alternative.

But if the federal exchanges were to lose their subsidies, everything would change. The New Jersey electorate would not be one to peaceably return to the bad old days of health care insecurity. Note that the subsidies go to people with incomes up to 400 percent of the federal poverty level — well into the middle class.

Experts on the health care law say that politicians such as Christie could finesse the matter by setting up a sort of state-run exchange. The law’s definition of state-run is so vague that a few changes could qualify an exchange as such — assuming the Obama administration would go along.

Of course, that would mean the politician could no longer pretend to be a bulwark against the encroachment of Obamacare. Christie has already broken with others in his party by signing on to the Medicaid expansion.

The court case revolves around a sloppily written passage in the law. The intent was obvious — that the subsidies would be extended to the state-run and federal-run exchanges alike — and the justices acted frivolously in even taking up this case.

One suspects that the Republican leadership regards this challenge to the Affordable Care Act as a great inconvenience. If the justices were to rule against the federal exchange subsidies, they would in effect be calling the politicians’ bluff. But if they were to rule in favor, that would take the alleged Obamacare foes off the hook.

One prefers the latter, but the former would be real interesting.

Froma Harrop is a syndicated columnist. Follow her on Twitter @FromaHarrop. She can be reached by email at: fharrop@gmail.com.