Image credit: Charles Dharapak/AP Photo

SALEM, Va. - Mitt Romney said today that President Obama's time in office will have been "wasted" if the Supreme Court rules his health care plan to be unconstitutional.

"As you know, the Supreme Court is gonna be dealing with whether or not Obamacare's constitutional," said Romney, previewing the court's decision that is expected to be announced on Thursday.

"If it's not, if Obamacare is not deemed constitutional, then the first three and a half years of this president's term will have been wasted on something that has not helped the American people," said Romney, offering his most scathing review to date of Obama's tenure should the plan be struck down.

"If it's not," Romney went on, "If it is deemed to stand, then I'll tell you one thing. Then we'll have to have a president, and I'm that one, that's gonna get rid of Obamacare."

"We're gonna stop it on day one," said Romney, appearing at a rally in the battleground state of Virginia, his first trip back since early May.

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Romney also offered his thoughts on yesterday's immigration ruling by the Supreme Court, the first time he has done so on camera since the ruling, saying that the work by the court "highlights the leadership failures of our current president."

"The Supreme Court had to step in because states had to step in, states looking to find a way to solve the problems [Obama] didn't address, tried to address it in their own ways, and now the Supreme Court's looked at it, and what we're left with is a bit of a muddle, but what we know is the president failed to lead," said Romney.