By Adam Serwer

The group seeking to invalidate the Affordable Care Act’s subsidies to Americans purchasing health insurance through federally run state marketplaces is asking the Supreme Court to take up the case early.

The Competitive Enterprise Institute, the conservative group funding challenges to the IRS rule allowing subsidies to flow to state exchanges, announced Thursday that it was asking the Supreme Court to intervene.

The challengers argue that the Affordable Care Act only allows subsidies in exchanges set up by states – an interpretation that could lead to millions of people being unable to afford coverage. Owing largely to Republican resistance, only 14 states have set up their own exchanges. The federal government runs the remaining 36.

Two federal courts split on the question last week, with a three-judge panel on the U.S. Court of Appeals for the Fourth Circuit  upholding the rule, and a separate three-judge panel on the U.S. Court of Appeals for the D.C. Circuit striking it down. 

That split may not last long, however, which may be one reason why the challengers are asking the Supreme Court to take the case. The Supreme Court is more likely to take cases if there are two contradictory decisions by federal appeals courts – what’s known as a “circuit split.”

The Obama administration has said it will seek review of the D.C. Circuit decision by the full slate of judges, known as an “en banc” hearing. If that happens, the previous decision will technically be wiped out, and there will be no more circuit split.

Some legal experts believe the full panel to be more sympathetic to the Obama administration, because the majority of judges are now Democratic appointees, thanks to Senate Democrats abolishing the filibuster for judicial nominations. 

“In a normal case, the Supreme Court would give the D.C. Circuit a chance to resolve the split,” said Brianne Gorod of the liberal Constitutional Accountability Center. “When the full D.C. Circuit decides the case, there probably won’t be a split, and then there will be no reason for the Supreme Court to get involved.”

For that reason, some legal experts, like Rebecca Buckwalter-Poza, believe the Affordable Care Act may be safer than it appears. 

Rick Hasen, a law professor at theUniversity of California-Irvine, said he didn’t think the Supreme Court would take the case quite yet.

“I think there’s no question that given the rush to get this in the opponents of the ACA want to give the Court’s conservatives a chance to grab this case early if they want,” said Hasen.  ”I don’t think that the court is likely to act while there’s an active en banc in the D.C. Circuit.”

The question, then, is whether there are at least four judges on the Supreme Court who are so eager to gut the Affordable Care Act’s subsidies, and so confident they have the votes to do so, that they’d take the case early.