Oral arguments begin Monday in the case that could both deflate the might of Congress and harm Obama's re-election chances this November.
Five of the nine Supreme Court justices were appointed by Republican presidents, leading some to assume the deck is stacked against Obama and that a high-profile humiliation awaits him just a few months before the presidential election.
David Plouffe, a chief Obama strategist, was putting on a brave face on the eve of the hearings as he made the rounds of the Sunday morning talk shows.
"We're confident that it's going to be upheld," Plouffe said on ABC's "This Week." "You had Democratic and Republican jurists uphold it in lower court decisions, including two very prominent conservative jurists."
He suggested that in the years to come, Republicans would live to regret opposing the law and appearing as though they were on the wrong side of history after the lives of millions are improved by the legislation.
"We're going to be glad the Republicans called it Obamacare," he said, adding only a "small portion" of Americans are now enjoying the perks of the new laws, but countless more will benefit by the end of the decade.
Obama's aim was true when he pushed for expansive health-care reform soon after his inauguration in early 2009.
The new law was directed at extending health coverage to more than 30 million uninsured Americans, outlawing health insurers from discriminating against people with costly conditions and preventing people from going bankrupt in the event they fell ill or suffered injuries while either uninsured or denied coverage.
But the requirement that most Americans buy health insurance or pay a penalty — the so-called individual mandate — is the most controversial element of the 2,700-page Patient Protection and Affordable Care Act, perhaps understandably so in a nation with a historical distrust of big government.
Three federal judges stateside have already struck down the individual mandate as unconstitutional, while three others have upheld it.
Now it's the Supreme Court's turn to decide whether to strike down or uphold the biggest expansion in America's social safety net since President Lyndon B. Johnson implemented Medicare and Medicaid in the 1960s. The panel is expected to hand down its final decision in June, just five months before the presidential election.
The six hours of argument time this week is the most scheduled by the court in 40 years. Court officials will also release audio recordings of the arguments shortly after they happen, a rarity that started during the Bush v. Gore case that settled the 2000 presidential election.
The House of Representatives narrowly approved Obama's health-care legislation in March 2010 in a 219-212 vote. The Senate then voted 60-39 following an often toxic national brawl that frequently saw Canada's own hallowed public health-care system alternately demonized as dreaded socialism and celebrated as a Utopian inspiration.
Republicans continue to rail against it, both on the campaign trail and on Capitol Hill.
"You know, the vice-president whispered to the president when they signed the bill two years ago: 'This is a big effing deal,'" Sen. Lindsey Graham of South Carolina said on CNN on Sunday.
"Well, now it has become a big effing mess for the Democratic Party and the country as a whole."
But in fact, the law has already benefited millions in the two years since its implementation.
It's given insurance coverage to more than 2.6 million previously uninsured young Americans, cut prescription costs by a total of US$3 billion for millions of senior citizens and eliminated so-called co-pays on preventive measures such as child immunizations and cancer screenings.
By 2014, when its most sweeping provisions kick in, millions more Americans will no longer have to worry that their health insurer can deny them coverage or hike their premiums if they fall ill or suffer injuries.
Poll after poll, however, suggest Democrats have done a terrible job educating Americans about the benefits of the new laws.
Americans are almost evenly divided about the legislation, with public opinion polls repeatedly showing them about 50-50 for and against.
A recent Kaiser Family Foundation survey found that only 39 per cent of those polled believed they had enough information about the law to understand how it was a boon to them personally, and that number had declined over the previous year.
Only one quarter of respondents were aware that the legislation had eliminated co-pays for preventative care and slashed the price of medication for seniors on Medicare.
Among those challenging the law at the Supreme Court are 26 states, the National Federation of Independent Business and a handful of individuals. More than 150 legal briefs have been filed by hundreds of lawyers, advocates for and against the law.
The six hours of arguments before the highest court in the land begin Monday morning and conclude mid-day Wednesday.
They'll delve into key legal questions surrounding the law, including whether Congress can force individuals to buy insurance and if lawmakers can pressure states to expand Medicaid coverage by threatening to withhold funds.
But at the heart of the debate is a broader question constitutional lawyers have been grappling with for more than 200 years: How much power does the Constitution grant Congress?
The Constitution's commerce clause authorizes Congress to "regulate commerce ... among the several states." The Constitution also allows Congress to pass laws that are "necessary and proper" to exercise its authority.
For decades, the Supreme Court took a broad, liberal view of those clauses. But in recent years, Congress has often been slapped down by the conservative majority on the panel.
In 1995, for example, the court struck down a federal law regulating guns near schools.
The Obama administration, however, argues that the health-care laws do in fact regulate commerce in the U.S. since they have a positive impact on the national economy.
The law "will improve the functioning of the national market for health care," Solicitor General Donald Verrilli Jr., the man who will defend the law to the Supreme Court, has argued in a brief.
There are political implications to the debate too, regardless of how the Supreme Court ultimately rules.
While some speculate Obama will be hurt if the court strikes down the law, others believe it will suggest the Supreme Court is hopelessly partisan, a state of affairs that could anger his base and propel them to the voting booths in November.
The entire health-care law debate also puts Republican frontrunner Mitt Romney in a tricky spot. If health-care reform becomes a big election issue, there's little doubt Obama will point to the individual mandate that Romney himself implemented in Massachusetts as governor.
Romney "is the godfather of our health-care plan," Plouffe said Sunday, accusing the candidate of unsuccessfully "running away from his past."