McCain Responds To New Romney Attack Ad: "Never Get Into A Wrestling Match With A Pig"

BURLINGTON, Iowa - The sprint for the Republican nomination took a turn down a negative path Saturday as contenders sought to point out their rivals' flaws only four days before the caucuses here and 10 days before New Hampshire's first-in-the-nation primary.

Political advertisements filled the airwaves in both early states, and contender Mitt Romney unleashed a new spot critical of Arizona Sen. John McCain as well as fliers and a TV ad slamming former Arkansas Gov. Mike Huckabee.

"McCain championed a bill to let every illegal immigrant stay in America permanently," an announcer says in the newest Romney ad airing in New Hampshire. "He even voted to allow illegal immigrants to collect Social Security. . . . On illegal immigration, there's a big difference."

Asked how he would respond, McCain told reporters traveling with him in New Hampshire: "Never get into a wrestling match with a pig. You both get dirty - and the pig likes it."

The Boston Globe reported McCain then clarified that he wasn't calling Romney a pig, just speaking generally about American politics.

The Washington Post's Howard Kurtz wrote in a Web posting that Romney was running the most negative campaign of any presidential candidate.

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