Texas Rep. Ron Paul is now on the air in Iowa with television ads attacking former House Speaker Newt Gingrich, making him the first candidate to go negative against the frontrunner in the Hawkeye State.

With former Massachusetts governoer Mitt Romney still struggling to decide how hard to push in Iowa, Paul is clearly positioning himself as Gingrich’s chief rival in the state.

A brutal two-minute web video, which the Paul campaign debuted last week, that depicts Gingrich as a flip-flopper and hypocrite has been cut down to a one-minute television ad.

“While the [web] video version of ‘Serial Hypocrisy’ had gone viral, the fact is we believe more people in Iowa deserve to know about Newt Gingrich's work in Washington,” said a senior Paul adviser.

Paul has actually run a far more aggressive campaign in Iowa than many of the more establishment candidates. For months, Paul had the airwaves to himself, and he’s spent more than $1.3 million on ads there. More Iowans also reported getting direct contact from his campaign than from any other candidate.

That work has paid off. In the latest Des Moines Register poll, he came in second to Gingrich in the state. In a Washington Post-ABC News poll conducted around the same time, Paul tied Romney for second.

Of the candidates currently in the top tier in Iowa, Gingrich and Paul are the ones competing for conservative and tea party votes. So it makes sense that Paul would be the first to take on Gingrich.

The Paul ad comes out the same day Glenn Beck did a tough interview with Gingrich, highlighting his past positions on the individual health-care mandate, ethanol subsidies, and cap-and-trade legislation.

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