BOSTON (CBS/AP) – The Supreme Court finished the first of three days of arguments Monday over whether President Barack Obama’s overhaul of the nation’s health care system is constitutional.

LISTEN: Supreme Court Audio

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Under the new law, taxpayers who don’t purchase health insurance will have to report that omission on tax returns for 2014 and will pay a penalty along with federal income tax.

At issue is whether that penalty is a tax.

26 states are challenging the federal health care law. The Supreme Court is hearing six hours of arguments over three days.

Republican presidential candidate Mitt Romney put in place a similar law in Massachusetts when he was governor, including a requirement that all residents buy health insurance.

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A similar so-called “individual mandate” in Obama’s law has drawn the ire of conservatives, including Romney’s opponent Rick Santorum.

Public polls, however, suggest that the vast majority of Massachusetts residents support the state health care system that Romney signed into law here in 2006.

But two years after the federal law was enacted, Americans remain skeptical about it, according to a CBS News/New York Times poll.

It shows 47 percent of Americans disapprove of the president’s Affordable Care Act, including 30 percent who strongly disapprove.

In the poll, conducted March 21-25, only 36 percent of those questioned said they support the law either somewhat or strongly.

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