The anti-Obamacare campaign is running out of options.

The Supreme Court's ruling Thursday in King v. Burwell was more than just another setback for critics of the health-care law: King might have been their last good opportunity to strike the Affordable Care Act at its core—to prevent it from becoming absorbed into the bedrock of the U.S. health-care system.

Congressional Republicans and the GOP's presidential contenders reiterated Thursday that they're committed to repealing the law. But, realistically, their best opportunities to kill or weaken Obamacare have always come from the courts—and that door appears to be closing.

"It's going to be more difficult. This would have been a lot easier to repeal and replace what was left of Obamacare if the Supreme Court would have ruled as the law was written and we could have enacted my proposal that would've cleaned up the mess," said Sen. Ron Johnson, one of the Republican lawmakers who had been working on a "fix" in case the administration lost King.

Simply put, the courts always have been Republicans' best bet because Obama is president. No bill to repeal the law has ever stood a chance, but there was a very real chance the Supreme Court would throw out the entire thing in 2012. And Obama would not any sign bill that chips away at core pieces of the Affordable Care Act—unless the ruling in King had forced his hand.

"I think this is pretty much the end of the line for Affordable Care Act litigation," said Timothy Jost, a law professor at Washington and Lee University and a strong supporter of Obamacare.

Obamacare has spent most of its five-year existence under the shadow of things that could kill or severely maim it. But every time it has escaped death's door, the next potential threat has gotten a little bit smaller.

In 2010, the threat was that Republicans would kill Obamacare in Congress and it would never even become a law. In 2012, it was that the Supreme Court could throw out the entire thing. Or if not the whole thing, at least one of its core provisions. A Romney presidency wasn't nearly as clear a shot as the Supreme Court could have been, but it was something. And then there was King—which could have done real damage, but never put full repeal on the table.

Now, Obamacare is out from under the shadow of major harm at least until January 2017—by far the longest such stretch it has enjoyed.

There are still anti-Obamacare lawsuits out there, and there will almost certainly be more, and some of them will succeed. But most of them challenge marginal or stand-alone pieces of the law, like its contraception mandate.

Two federal appeals courts have dismissed lawsuits challenging Obamacare on the grounds that it originated in the Senate, while the Constitution requires revenue-raising bills to originate in the House, and several courts have also dismissed new challenges to the individual mandate. The Supreme Court has refused to hear a suit challenging a cost-cutting board created by the health-care law—but even if that particular challenge can be revived in the future, the rest of the law would be untoched.

Republicans' best bet in the courts probably comes from the House's lawsuit against Obama, challenging the way that his administration has administered a separate type of subsidy. If it succeeds, that suit could wipe out a substantial chunk of financial assistance provided by the health-care law. But that case still is in the early stages, and many legal experts are skeptical the House will ultimately have legal standing to sue the administration.

Even many congressional Republicans conceded Thursday that, post-King, anything substantively anti-Obamacare will probably have to wait until after 2016—meaning not only that a Republican would have to win the White House, and that Republicans would have to keep control of Congress, but that those officials would have to remain committed to repealing the Affordable Care Act even as it grows more established and covers more people.

In 2017, according to the Congressional Budget Office's latest estimates, some 24 million people will likely be covered under Obamacare's insurance exchanges, and another 12 million under its Medicaid expansion.

The bigger that number gets, and the longer Obamacare stays the law of the land—even if it remains politically unpopular—the harder it'll be for elected officials to take away those benefits.

Which is why they could have used some help from the Supreme Court.


Caitlin Owens contributed to this article

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