If sometimes it seems like the two candidates for president are speaking different languages, the reason is simple:

They are.

President Barack Obama and Mitt Romney use distinct vocabularies. Each has a campaign glossary of sorts to define himself, criticize the other guy, highlight opposing economic philosophies.

Fair shot or economic freedom? The nation's welfare or class warfare? You're-on-your-own economics or the heavy hand of government?

The president has tried to cast himself as the champion of the middle class. He claims Romney wants to perpetuate failed economic policies that favor the rich and privileged business interests over everyday workers. Obama regularly denounces tax breaks for millionaires and billionaires and frequently talks about the importance of "playing by the rules."

Romney has portrayed himself as Mr. Turnaround, the hands-on guy whose 25 years in the private sector give him the ideal resume to revive an economy he contends has gone from bad to worse under the president. His speeches are filled with patriotic references to the Founding Fathers and regular mentions of "free enterprise" and "prosperity."

"In a lot of ways, it's the standard party line Democrat, working-class rhetoric, Republican, business class," says Mitchell McKinney, professor of communication at the University of Missouri.

"Both are playing to the base. ... Obama has to address those disparities in the economy without seeming that he is anti-business, anti-capitalist. ... Romney wants to tout the making of money and successful working of the capitalist system but not highlight in any way the downside. In that sense they both have fine lines they're trying to walk."

Both men have tripped on their own rhetoric.

There was Obama's recent retreat from his assertion that "the private sector is doing fine" and Romney's declaration that "corporations are people." In coming months, McKinney says, the candidates, surrogates and big-money political groups will repeat certain words and phrases "so America comes to accept their narrative as reality. Clearly, words do matter."

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Fair shot, freedom, class warfare: Economic glossary of campaign '12 shows big divide