The looming Supreme Court decision on ObamaCare is expected to shake up the presidential campaign, no matter which way the justices rule. The decision, which will come any day between now and June 29, could obliterate President Obama's signature domestic policy achievement in one fell swoop, or instantly discredit Republican complaints that the health-care reform law's central component, the individual mandate to buy insurance coverage, is unconstitutional. The Obama and Romney campaigns are both expected to immediately try spinning the ruling to their advantage. The question is, will the Supreme Court's final word on the Affordable Care Act give Obama an edge in November, or help push Romney over the top? Here, four possible scenarios:

If the Supreme Court strikes down ObamaCare...

Obama will be in big trouble: A loss for ObamaCare, says John Hinderaker at Power Line, would "confirm in voters' minds that Obama took his eye off the ball by focusing on health care rather than the economy during the first year of his administration." It would embarrass the president, and erase what was supposedly Obama's "signature achievement," and one of his few big legislative wins. If a year-long push to pass ObamaCare "turns out to have been for naught, how can it possibly make Obama look good?"

Democrats will be fired up: If the court invalidates all of the Affordable Care Act, or even just some key parts, says John Sivolella at Boston Magazine, "the Obama campaign will pounce, making the court itself an issue in the campaign." That could help put Obama over the top by firing up the Democratic base, and delivering his campaign "another huge opportunity to promote its apparent slogan for November: 'It's anything but the economy, stupid!'"

If the Supreme Court upholds ObamaCare...

Romney will rally anti-ObamaCare voters: "It's easy to see why Republicans might think the law surviving is good for them," says Jonathan Allen at Politico. More than two-thirds of Americans think the court should strike down some or all of the health-care overhaul. If it's allowed to stand, many voters would be furious, and Romney would be able to draw "a much clearer contrast with Obama on health care. Obama wrote the Affordable Care Act; Romney is campaigning to repeal it."

Obama will breathe a sigh of relief: Forget all the contrarian "nonsense" about how Obama or Romney will win by losing, says Jeffrey Toobin at The New Yorker. "In politics and the rest of life, it's always better to win than lose. Winners win, and losers lose." There's no doubt that Obama and his allies would "trumpet the decision as vindication of their efforts," says James C. Capretta at Economics 21, and argue that it is "time for opponents to 'move on' from their intransigence."

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