US Supreme Court Justices (front l-r ): Clarence Thomas, Antonin Scalia, Chief Justice John Roberts, Anthony M. Kennedy, and Ruth Bader Ginsburg (back l-r): Sonia Sotomayor, Stephen Breyer, Samuel Alito Jr., and Elena Kagan
WASHINGTON (CBS NEWS) - The Supreme Court is poised to announce a decision this week - perhaps as early as today - that could affect the political landscape, the economy, and the lives of millions of Americans.
As the court winds up its term, the justices are expected to announce their ruling on whether President Obama's health care law, the Affordable Care Act, considered by most to be his signature achievement, is constitutional.
It's seen as the most significant health care legislation in 40 years or, as Vice President Biden whispered in Mr. Obama's ear when it was passed in March 2010, "This is a big [expletive] deal.
And with word on the ruling due any day, Democrats and Republicans are fine-tuning their message.
Earlier this month, House Speaker John Boehner said, "We know that it must be repealed in its entirety."
But former House speaker and now House Minority Leader Nancy Pelosi told "CBS This Morning" co-host Charlie Rose earlier this month, "I think we're ironclad on the constitutionality of the bill."
Since the law passed, millions have taken advantage of some provisions already in place, such as coverage for adult children up to the age of 26 by their parents' insurance.
But the court must decide whether an unpopular part of the law, the requirement that all Americans have health insurance or pay a penalty, known as the individual mandate, is constitutional.
The potential outcomes range from the court upholding the law in its entirety, striking down the controversial individual mandate and leaving the rest - or most - of the law in place, or declaring the entire bill unconstitutional.
Presumptive GOP presidential nominee Mitt Romney says if the court upholds any part of the law, he'll work to eliminate it.
"Regardless of what they do, it's going to be up to the next president to either repeal and replace Obamacare, or replace Obamacare," Romney says.
The president has made his views clear on what the court should do, saying, "I am confident that this will be upheld because it should be upheld."
But he hasn't said what he will do if it's struck down.
White House officials have indicated they will try to implement whatever's left.
And candidates up and down the ticket, in Washington and elsewhere, also are preparing for decision day.
Indiana Senate candidate Richard Mourdock is ready for any scenario - his campaign accidentally released videos he'd filmed to cover every possible outcome.
Among his statements in the videos: "Well, we've had our brief moment of celebration because the Supreme Court ruled that Obamacare is in fact unconstitutional"; "We now know that Obamacare came down as a split decision"; "They've ruled that Obamacare is constitutional."
Meantime, no one in Washington seems able to agree on who'd win and who'd lose no matter what the justices rule.