The cases are merely the top of a pile of Obamacare-related litigation in U.S. courts. | John Shinkle/POLITICO Obamacare and SCOTUS, the sequel?

The U.S. Supreme Court will begin its new term Monday and, once again, Obamacare could be on the docket.

The justices have been asked to weigh in on whether the Affordable Care Act’s subsidies can go to any American, regardless of whether their state runs a health insurance exchange or relies on the federal one. They’ll soon be asked, too, whether religious nonprofits have to provide contraception in employee health plans, a follow-up to last spring’s Hobby Lobby case.


And there is a third, very long-shot issue in the wings: whether the health care legislation was a tax bill that under the Constitution had to start in the House of Representatives instead of the Senate.

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The cases are merely the top of a pile of Obamacare-related litigation in courts around the country. The legal fights just keep growing, more than four years after the law was passed, more than two years after the Supreme Court issued its landmark June 2012 decision upholding the unpopular individual mandate and more than a year after millions of Americans started signing up for the health benefits.

Most of the lawsuits stand little chance of seriously damaging the health law, let alone killing it.

The exception — the challenges over the subsidies, or tax credits — could strike at a core tool for expanding insurance coverage to millions of people who got subsidized coverage through HealthCare.gov when their governors would not or could not run a state exchange. That set of cases is often referred to as “Halbig,” after one of the plaintiffs. The legal argument was once seen as a fringe issue, a last gasp of opposition. But now, if the Supreme Court takes up the issue, it would represent a serious legal challenge to President Barack Obama’s signature domestic legislation.

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Other cases now working their way through the courts take on everything from the employer mandate to a Medicare spending board to deciding who is responsible for Oregon’s failed exchange.

On the subsidies case, the challengers say that the exact wording of two parts of the law makes clear that subsidies are only allowed to go to residents of states with state-based exchanges. Obamacare backers say a thorough reading of the entire law makes clear that anyone can get subsidies, even if they live in a state that is using the federal exchange.

Lower courts have split, with two circuit courts memorably ruling opposite ways on the issue within a few hours. That kind of circuit split is typically a lock for getting strong consideration by the justices. But one of the courts — the D.C. Circuit, which ruled against the Obama administration — recently agreed to hear the case again in a rare en banc hearing.

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The conventional wisdom is that the second hearing, which includes all of the court’s judges, not just the three who heard the case originally, will go for the Obama administration.

But the Supreme Court doesn’t have to wait for the en banc hearing in December and a decision likely months later. The plaintiffs that lost in the other case, which went through the 4th Circuit Court of Appeals in Richmond, have already asked the justices to weigh in.

Michael Carvin, the attorney representing the challengers, says he doubts that four Supreme Court justices will care what the D.C. Circuit — which is packed with Obama-appointed judges, he says — thinks about the case.

“I think the calculus among the justices up there will be if the D.C. Circuit, particularly along strictly partisan lines, agrees with the Obama administration, is that really going to affect our view of the underlying issue? If we don’t believe that’s true, we might as well take the 4th Circuit case now and decide it,” Carvin said last week at a Supreme Court event hosted by The Heritage Foundation.

Conservatives were also buoyed by a district court ruling in their direction this week. A federal judge in Oklahoma said Tuesday that the subsidies can go only to federal exchange states, but he indicated in his ruling that he expects the decision to be immediately appealed to the 10th Circuit.

Other legal experts say the Supreme Court justices will be cautious before wading back into the choppy waters of another highly controversial Obamacare case.

“I really believe the Supreme Court will wait and see what the D.C. Circuit does,” said Timothy Jost, a Washington and Lee University law professor who supports the health law. “The absence of a circuit split makes it even less likely they’ll take it.”

Martin Lederman, a Georgetown University law professor and former Justice Department official, agreed that a circuit split is likely the only condition under which the court would accept the tax subsidy issue.

“If, at the end of the process, there is a split among circuits, the Supreme Court is very likely to take the case. In fact, all sides will be asking the Supreme Court to take it,” he said. “If, on the other hand, at the end of the process the D.C. and 10th circuits agree with the 4th, it is much less likely that the court will take it and least likely at all is that the court will [accept the case] before hearing from those circuits.”

The Obama administration has until Friday to reply to the 4th Circuit petition.

One other lawsuit challenges the federal exchange subsidies, but it is not nearly as far along in the legal process. A federal judge in Indiana will hear the case next week.

The tax subsidy case could be a blockbuster because it would put the health law’s subsidies on the line. But there is another ACA-related case the court is more likely to take. It’s essentially part two of the Hobby Lobby decision handed down on June 30.

Hobby Lobby questioned whether for-profit companies have to provide contraception in employee health plans — and the court said some businesses run by owners with strong religious objections should be exempt. This pending case asks whether nonprofit religious institutions, such as Catholic schools, have to abide by the requirement.

The first of at least two expected petitions — from the University of Notre Dame — is due this week. A stream of other petitions is expected to follow in coming months as appeals courts weigh the issue.

Finally, there is a third case on the Supreme Court’s doorstep. The justices have been asked to review Obamacare’s constitutional legitimacy because, according to the challengers, the bill that became the health law started in the Senate and not the House.

The suit, brought by the Association of American Physicians and Surgeons, was dismissed twice in the lower courts, and there are few reasons to believe the justices will accept the case as the group requested late last week.

Other potential sleeper issues are lurking in appeals courts as well.

An appeals court in Atlanta will hear oral arguments in mid-October on whether the law’s employer mandate is valid. A Chicago appeals court is weighing a lawsuit brought by Sen. Ron Johnson (R-Wis.) on the law’s requirement that members of Congress enroll in Affordable Care Act plans that can be partially paid by the federal government.

And the Supreme Court could be asked as soon as this month to review a case that challenges the health law’s Medicare spending board, called the Independent Payment Advisory Board.