Ron Paul ad says Santorum is 'fake' conservative

A new Ron Paul ad says that Rick Santorum voted to double the size of the Department of Education. Why is Ron Paul hammering Santorum instead of Mitt Romney? credentials.

TITLE: "Fake"

LENGTH: 30 seconds.

AIRING: On broadcast and cable in Michigan.

KEY IMAGES: Splashy sound effects and cut-outs of Rick Santorum are overlaid on a series of images designed to question the former Pennsylvania senator's credentials as a fiscal conservative. A male narrator asks: "Is this dude serious? Fiscal conservative? Really? Santorum voted to raise the debt ceiling five times, doubled the size of the Department of Education, then supported the biggest entitlement expansion since the '60s."

He continues: "Not groovy. Santorum voted to send billions of our tax dollars to dictators in North Korea and Egypt. And even hooked Planned Parenthood up with a few million bucks. Rick Santorum, a fiscal conservative? Fake."

ANALYSIS: Tied or leading in a slew of national and state polls, Santorum is now taking fire from all sides. With super PAC groups supporting former Massachusetts Gov. Mitt Romney already pouring millions into attack ads against him, Santorum is now taking fire from Rep. Ron Paul, a candidate with money to burn and, most believe, no chance of winning the Republican nomination.

RELATED: 7 culture war moments of Rick Santorum

The ad uses a series of comical images and a flippant tone to chip away at Santorum's core credentials as a conservative. While Santorum would probably dispute the way the material is cast, its facts are correct. As a senator and congressman, Santorum voted to raise the debt ceiling several times. He supported increased funding to the Education Department and has previously supported expansion of entitlements. Bills he voted for did send aid abroad and did give money to Planned Parenthood. But these funds were a part of much larger spending bills, an important nuance.

Beyond the merits of Paul's specific attack, the more interesting question may be why Paul is targeting Santorum and not Romney. As the GOP race has unfolded Paul has refrained from attacking Romney. But he has periodically risen to swat at other contenders, including former House Speaker Newt Gingrich.

One explanation is that Paul, who has said pursuing delegates and finding a broader platform for his limited government message are his chief goals in the GOP race, is avoiding attacks on Romney because he believes that Romney will be the eventual GOP nominee. Paul could be courting favor with the likely nominee in the hope that he will give him a more prominent role in the party.

Whatever Paul's reasoning, the ad is bad news for Santorum. With limited funds for counterattacks, he's now taking hits from all sides.

RELATED: 7 culture war moments of Rick Santorum