STERLING, Va. - On the eve of the Supreme Court's decision as to whether President Obama's health care law is constitutional, Mitt Romney bounded into the battleground state of Virginia and predicted a sleepless night in the White House.

"[It's] very clear that a big decision is coming tomorrow for the Supreme Court," said Romney at a raucous rally in northern Virginia this evening. "My guess is they're not sleeping real well at the White House tonight. That's the way it ought to be.

"And this is a decision, by the way, about whether or not 'Obamacare' is constitutional," said Romney. "Whether it passes constitutional muster. And so we're all waiting to see how the court will decide. One thing we already know, however, we already know it's bad policy and it's gotta go."

Romney, who said Tuesday that Obama's term would be "wasted" if his signature plan is struck down by the nation's highest court, said today that if the plan is ruled unconstitutional, some of his own work will be taken care of for him.

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"And so if the court upholds it, if they say, look, it passes the constitution, it still is bad policy and that'll mean if I'm elected we are going to repeal and replace it," said Romney, who spoke to a notably energetic crowd of hundreds at an electrical manufacturer. "And if, on the other hand, the court strikes it down, they'll be doing some of my work for me, I won't have to repeal it, but I still will have to replace it and I will!

"So for these among many other reasons, whatever the Supreme Court does tomorrow, one thing we know: If I'm elected president, we're gonna get rid of 'Obamacare' and replace it with real reform," said Romney, not delving into what said "real reform" would entail.

Romney, who unexpectedly appeared alongside Gov. Bob McDonnell, a man some say may be considered as the candidate's running mate, continued to paint the White House as a home that will soon be filled with insomniacs, adding that "There are going to be a lot of sleepless nights at the White House over the next few months because the president's in a tight spot.

"He's in a tight spot because of 'Obamacare' and the fact the American people don't want it and the more they learn about it, the less they like it," said Romney. "He's in a tight spot because he hasn't done what he said he'd do."