There's a McCain on the campaign trail . . .McCain Foods USA , that is. Playing off a presidential candidate of the same name, this Lisle, Ill.-based company (a competitor to H.J. Heinz Co.'s Ore-Ida brand)  developed print and online ads for its own frozen potato products. Advertising Age reported that one full-page ad breaking on Aug. 29 inUSATodayis titled, "Why McCain should be in the White House." "We were looking at how to make our ad dollars work harder for us with breakthrough advertising in a Olympic and [election] year," said Frank Finn, McCain's senior vice president of commercial operations. Finn said McCain also has hired "Mad TV" star and impersonator Frank Caliendo to do his best John McCain for on-the-street videos, which will be broadcast on the company's Web site and on YouTube.