Washington ? The Supreme Court’s ruling on the constitutionality of President Barack Obama’s health care overhaul is likely to shake the presidential election race in early summer. But the winners in the court will not necessarily be the winners in the political arena.

No doubt, a decision to throw out the entire law would be a defeat for Obama. His judgment and leadership, even his reputation as a former constitutional law professor, would be called into question for pushing through a contentious and partisan health insurance overhaul only to see it declared unconstitutional by the court.

But it would not spell certain doom for his re-election. In fact, it would end the GOP argument that a Republican president must be elected to guarantee repeal of the law. It also could re-energize liberals, shift the spotlight onto insurance companies and reignite a debate about how to best provide health care.

Upholding the law

If the court upholds the law, Obama would be vindicated legally. Republican constitutional criticisms would be undercut because five of the nine justices were nominated by Republican presidents.

But opposition would intensify in the political world. Without legal recourse, Republicans would gain new energy to argue that the only path to kill the law would be to elect a Republican president and enough GOP candidates to control the House and Senate. They might be wary of promising overnight repeal because a filibuster-proof Senate majority seems beyond their reach in the November election.

Central to the dispute over the law is a provision that requires individuals to have health insurance by 2014 or pay a penalty. Polls show that this mandate is opposed by 3 of 5 Americans. Among Republicans, calls for its repeal are a surefire applause line.

Of the four federal appeals courts that have ruled, two upheld the law, one struck down only the insurance mandate and one punted, saying an obscure tax law makes it premature to decide the merits until the main coverage provisions take effect in 2014.

Possible outcomes

With the court hearing arguments Monday through Wednesday, operatives from both parties have been playing out the potential outcomes. It’s a calculation complicated by the intensely polarized public attitudes toward the law, by the still unsettled race for the Republican nomination and, most important, by the range of potential decisions by the court.

“A lot of the arguments that are being made against it right now are that they violate basic constitutional rights and principles,” said Tad Devine, a veteran consultant of Democratic presidential politics. “If the Supreme Court, controlled by Republicans, doesn’t agree with that, I think it’s going to be hard to make that argument.”

“If they strike down the mandate,” he added, “it takes away a lot of the attack against the president on that issue.”

White House and Obama campaign officials would not publicly discuss the options ahead, worried they would be perceived as trying to influence the court. But the Obama campaign has begun to draw attention to the benefits of the law, hoping to counter the beating the law has taken from the GOP presidential candidates.

This past week, it posted a new health care app online where users can find out how the health care law affects them. It also launched a website that features testimonials about the law.