Romney, one of the Republican candidates for president, was giving a speech at the Iowa State Fair in Des Moines.
Romney, a multimillionaire businessman who casts himself as a jobs creator, declared that "corporations are people" while outlining options for reducing the federal deficit and overhauling entitlement programs.
That comment drew ridicule from Democrats. Hecklers chanted "corporations," suggesting that they were the ones that should be taxed.
The Associated Press contributed to this story.