Texas Rep. Ron Paul (Gage Skidmore, Creative Commons)

Paul, who has spent most of his career in Congress, has already rocked the GOP race.

The latest Iowa poll puts Ron Paul at just a percent point from the new frontrunner in the state.

The Texas congressman has been nicknamed the "intellectual godfather" of the Tea Party movement. Paul favors cutting $1 trillion from the federal government, slashing the corporate tax rate and removing taxes on capital gains and dividens. He also supports the elimination of five federal cabinet agencies and strongly opposes federal health care, making him popular with groups that favor limited government.

Asked about earmarks during Thursday’s debate in Iowa, Paul said he has never voted for them, although he acknowledged using funds.

"I do argue the case for the people I represent to try and get their money back if at all possible," said Paul.

In a Thursday afternoon appearance on Fox News Paul attacked Newt Gingrich for allegedly dodging military service during the Vietnam War. Paul said Gingrich got several military deferments to avoid service.

"There was one other issue that I personally found annoying is that he's probably as aggressive with the military as anybody, he supports all the wars in the Middle East a thousand times more than I would," Paul told host Megyn Kelly.

Paul also defended a new web ad in which he calls Gingrich a “serial hypocrite.”

“Negative campaigning is calling people names, demagoguing issues … pointing out differences is my job,” Paul said.

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