WASHINGTON – The Supreme Court announced Monday that it will use an unprecedented week’s worth of argument time in late March to decide the constitutionality of President Obama’s historic health care overhaul before the 2012 presidential elections.

The high court scheduled arguments for March 26, 27 and 28 over the Patient Protection and Affordable Care Act, which aims to provide health insurance to more than 30 million previously uninsured Americans. The arguments fill the entire court calendar that week with nothing but debate over Obama’s signature domestic health care achievement.

With the March dates set, it means a final decision on the massive health care overhaul will likely come before Independence Day in the middle of Obama’s re-election campaign. The new law has been opposed by all of Obama’s prospective GOP rivals. Republicans have branded the law unconstitutional since before Obama signed it in a March 2010 ceremony.

The justices are hearing more than five hours of arguments over the health care overhaul. In the modern era, the last time the court increased that time anywhere near this much was in 2003 for consideration of the McCain-Feingold campaign finance overhaul. That case consumed four hours of argument.

The court will start the week of arguments that Monday with one hour on whether court action is premature because no one yet has paid a fine for not participating in the overhaul.

Tuesday’s arguments will take two hours, with lawyers debating the central issue of whether Congress overstepped its authority by requiring Americans to purchase health insurance starting in 2014 or pay a penalty.

Finally, Wednesday’s arguments will be split into two parts, with justices hearing 90 minutes of debate over whether the rest of the law can take effect even if the mandate is unconstitutional, and an hour of arguments over whether the law goes too far in coercing states to participate in the overhaul by threatening to cut off federal money.