WASHINGTON — The Supreme Court said today it will hear arguments in March over President Barack Obama’s health care overhaul — a case that could shake the political landscape just as voters are deciding if Obama deserves another term.

The decision to hear arguments in the spring allows plenty of time for a decision in late June, just more than four months before Election Day. This sets up an election-year showdown over the White House’s main domestic policy achievement.

The justices announced they will hear more than five hours of arguments, an extraordinarily long session, from lawyers on the constitutionality of a provision at the heart of the law and other related questions about the act. The central provision in question is the requirement that individuals buy health insurance starting in 2014 or pay a penalty.

The 2010 health care overhaul law aims to extend insurance coverage to more than 30 million Americans, through an expansion of Medicaid, the requirement that individuals buy health insurance starting in 2014 or pay a penalty and other measures.

By The Associated Press