WASHINGTON (AP) — House Republicans, stung by the Supreme Court decision upholding President Barack Obama's health care overhaul, are seizing on one wrinkle to bolster their election-year case for repeal — the court's judgment that the penalty for failing to get insurance is a tax.

The House has voted more than 30 times to scrap, defund or undercut the law since Obama signed it in March 2010, political moves that went nowhere in the Democratic-controlled Senate. Republican opponents cast the law as government overreach, socialized medicine and an unaffordable approach to the nation's system of health care.

Two weeks after the conservative-led court's ruling, the House GOP leadership pushed for another symbolic repeal vote on Wednesday with a fresh argument. Chief Justice John Roberts wrote in his majority opinion that the law was constitutional because it imposes a tax — not a penalty — on people who refuse to buy insurance. Republicans who repeatedly pressed for repeal said a "yes" vote would not only overturn the law but spare some 20 million Americans from an unnecessary tax.

The law's onerous burdens and taxes, Republicans complained, were stifling small businesses now reluctant to hire because of the additional expenses. This represented a clear obstacle to the country's economic recovery.

They also pointed out that Obama had promised not to raise taxes on the middle class, and the fee for failing to get insurance would do just that.

"As the Supreme Court ruled, the cornerstone of the Democrats' health care law, the individual mandate, is a massive tax," said House Ways and Means Committee Chairman Dave Camp, R-Mich., during the daylong debate Tuesday. "This is a major tax with major implications. Democrats have argued that the individual mandate was necessary to improve the nation's health. So what's next? Will they require you to purchase low-fat or low-salt foods or pay a tax because they think it's good for you?"

Democrats countered that the penalty for not buying insurance was directed at people who could afford it.

"Otherwise you're passing the cost on to us," said Rep. Jim McDermott, D-Wash. "You're a freeloader. The Republicans are glorifying freeloaders."

Under the law, Americans who don't get qualified health insurance will be required to pay the penalty — or tax — starting for the 2014 tax year, unless they are exempt because of low income, religious beliefs or because they are members of American Indian tribes. The penalty will be fully phased in by 2016, when it will be $695 for each uninsured adult or 2.5 percent of family income, whichever is greater, up to $12,500.

Democrats circulated a memorandum with a series of quotes from likely Republican presidential nominee Mitt Romney in which he defends the so-called individual mandate of the Massachusetts' health care law that he secured as governor. Obama's law was closely modeled on the universal-coverage plan that Romney instituted in his state. That plan penalized people who failed to comply with the requirement to buy insurance, just like the Obama overhaul will do.

Romney, the Democrats pointed out, said in June 2005 that "everyone must either become insured or maintain adequate savings to cover their medical expenses. We cannot expect some citizens to pay for others who can afford to pay some or all of their own way."

Democrats also argued that the two days of debate and vote were a waste of time because the Democratic-led Senate wouldn't vote for repeal, the Supreme Court had rendered its judgment and voters want Congress to focus on more pressing issues such as the sluggish economy.

"As a psychiatrist, I'm qualified to say this," McDermott said. "One definition of insanity is doing the same thing over and over again and expecting a different result. The game is over. The referee, John Roberts, blew the whistle. It's over, guys."

Although the outcome isn't in doubt, the vote provides plenty of election-year fodder, energizing the political base and helping to attract campaign dollars. House Whip Kevin McCarthy, R-Calif., said a number of Democrats would join Republicans in voting to repeal the law.

In fact, many of the Democrats who backed the overhaul lost their seats in the 2010 elections. Those who are left would be open to charges of flip-flopping if they switch their votes.

The health care law was Obama's signature domestic achievement, but it remains unpopular and divisive among the public according to opinion polls. Democrats argued that erasing the law would eliminate the more popular individual elements — a guarantee on coverage for those with pre-existing medical conditions, a requirement allowing children up to age 26 to remain on their parents' coverage and the reduction of seniors' Medicare prescription drug costs by closing the "doughnut hole" coverage gap.

Republicans insisted they were keeping a promise with Americans to repeal the law.

"This law epitomizes Washington at its very worst: intrusive mandates, higher costs, red tape, unaffordable spending, taxes on employers and families and control of personal health care decisions by boards, bureaus and agencies in Washington," said Rep. Fred Upton, R-Mich., chairman of the House Energy and Commerce Committee.

Aside from the criticism and the calls for "repeal and replace," the GOP did not offer any specific alternative to Obama's law.