Republican Presidential Hopefuls Unleash Arsenal Of New Ads

A new Gallup poll shows former Massachusetts Governor Mitt Romney and former House Speaker Newt Gingrich now tied nationally.

Gingrich has fallen 12 points since early December. The super PAC Winning Our Future hit the airwaves in support of Gingrich today, with an ad that warns "don't let the liberal republican establishment pick our candidate."

But Gingrich is being far outspent on the Iowa airwaves by Romney, and by Texas Congressman Ron Paul, who's now leading polls in Iowa. Paul debuted an ad Wednesday that labels Romney a "flip flopper" and Gingrich a "serial hypocrite," calling Paul "the one we've been looking for" because he is as "consistent, incorruptible, guided by faith and principle."