STORY HIGHLIGHTS

Washington (CNN) -- The U.S. Supreme Court will rule Thursday on the constitutionality of the sweeping health care law championed by President Barack Obama.

The high court announced a series of other decisions on Monday, but not the most anticipated one. It announced that all remaining rulings for the year will come in three days.

The stakes cannot be overstated -- what the justices decide will have an immediate and long-term impact on all Americans, both in how they get medicine and health care, and also in vast, yet unknown areas of "commerce."

Saving this ruling for the final day "may not be political, but they understand drama," said David Cole, a Georgetown University constitutional law professor. He added, "It's also the most difficult case, the most important case, so they may want the extra few days to make sure that they're happy with their written opinions."

The nation's highest court heard three days of politically charged hearings in March on the 2010 Patient Protection and Affordable Care Act, a landmark but controversial measure passed by congressional Democrats despite pitched Republican opposition.

The challenge focused primarily on the law's requirement that most Americans buy health insurance or pay a fine.

Supporters of the plan argued the "individual mandate" is necessary for the system to work, while critics argued it is an unconstitutional intrusion on individual freedom.

All sides preparing for political fallout from health care decision

Four different federal appeals courts heard challenges to parts of the law before the Supreme Court ruling, and came up with three different results.

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Health care ruling looms