Strong: having or marked by great physical power; having great resources.

Sound: solid; firm; stable.

That's how Merriam-Webster defines the two words that the White House says is the difference between what John McCain said on the campaign trail last year and what President Obama and his economic adviser Christina Romer said in the last few days when describing the fundamentals of the U.S. economy.

At the daily press briefing, Press Secretary Robert Gibbs noted a difference between the two. "Do I think there's a definitional difference between sound and strong? Absolutely," Gibbs said. "I think the fundamentals, as Ms. Romer said, are sound. That the President is taking steps each and every day to strengthen those fundamentals to ensure that the pillars that we need to turn our economy around to create the jobs the President talked about, to give the middle class finally a fair shake, and to put ourselves on a path toward sustained economic growth is exactly what the President is focused on each and every day."

However, the NRCC sees little difference and has issued a press release in 50 Democratic House districts questioning the potentially conflicting statements.

"Are the fundamentals of our economy strong or is the President of the United States just fundamentally wrong? That is the question Mary Jo Kilroy needs to answer," NRCC Communications Director Ken Spain is quoted saying in a press release to one of 50 House districts. "Does Kilroy stand by her Democrat colleagues who claimed that it was 'absurd' to say the fundamentals of the U.S. economy are sound or will she stand up to President Obama and tell him that he is sadly mistaken when it comes to the economic problems middle-class Americans are facing?"