A woman rings a bell as Obamacare supporters shout slogans in front of the U.S. Supreme Court March 28, 2012 in Washington, D.C. -- the last day the court heard arguments over the constitutionality of the Patient Protection and Affordable Care Act. Commentator Robert Reich says the health insurance lobby could unwittingly revive the "public option." - 

Any day now the Supreme Court will issue its ruling on the constitutionality of the Affordable Care Act, which even the White House now calls Obamacare.

Most observers of the High Court think it will strike down the provision of the act that requires almost everyone to buy health insurance -- the so called individual mandate -- as violating the Commerce Clause of the Constitution. The justices will likely leave the rest of the health care law intact.

But the individual mandate is so essential to spreading the risk and cost of health care over the whole population, including younger and healthier people, that some analysts believe a court decision that nixes the mandate will effectively spell the end of the act anyway.

Yet it's possible the exact opposite could happen -- thanks to the health insurance industry. If the court does what's expected, insurance lobbyists and executives will swarm Capitol Hill seeking to have the act amended to remove the requirement that they provide coverage to people with preexisting medical conditions. The insurers will argue that without the mandate they can't afford to cover those chronic ailments.

But the requirement to cover preexisting conditions has proven so popular with the public that Congress will be reluctant to scrap it.

This opens the way to a political bargain. Insurers might be let off the hook, for example, only if they support allowing every American, including those with preexisting conditions, to choose Medicare, or something very much like Medicare, for health care coverage. In effect, what was known as the "public option" during the debate over the bill.

So in striking down the individual mandate -- the least popular part of Obamacare -- the Supreme Court will inevitably bring into question the fate of its most popular part,coverage of pre-existing conditions. And in so doing, open alternative ways to maintain that coverage -- including ideas, like the public option, that were rejected in favor of the mandate.

The fact is, there's enough the public likes about Obamacare that if the court strikes down the individual mandate, that won't be the end. It will just be the end of the first round.