Santorum ad: Romney is an Obama clone

Hours before tonight's GOP presidential debate in South Carolina, Rick Santorum's campaign released an attack ad that suggests Mitt Romney is "just like Obama" - in part by citing his past positions on social issues.

"Obama supported the Wall Street bailouts - So did Romney," a narrator intones ominously, as images of the two men appear onscreen. "Obama gave us radical Obamacare - that was based on Romneycare. Obama's a liberal on social issues. Romney once bragged he's even more liberal than Ted Kennedy on social issues."

The spot concludes with the narrator asking: "Why would we ever vote for someone who is just like Obama? When we can unite around Rick Santorum. And beat Obama."

The Santorum campaign did not immediately respond to a request for a citation for the claim that Romney, who has shifted to the right on abortion and gay rights since his time as Massachusetts governor, "bragged he's even more liberal than Ted Kennedy on social issues."

The campaign said the ad would begin airing Wednesday in South Carolina ahead of the state's January 21 primary. The spot is the first negative ad from Santorum in the state; the campaign did not disclose how much it is spending to air it.

Santorum won the backing of a group of prominent social conservatives who met in Texas over the weekend, an endorsement he hopes will allow him to consolidate the support of conservatives who oppose frontrunner Romney as the GOP nominee. He is seeking an upset victory in South Carolina in part by appealing to the state's many social conservatives: In the 2008 GOP primary, 60 percent of South Carolina Republican primary voters identified as "born again" or evangelical Christians.

In its release heralding the spot, the Santorum campaign wrote that "unlike Mitt Romney and Barack Obama, Rick Santorum has been a proven fighter for the unborn and our nation's traditional values."

Santorum has notably declined to join Newt Gingrich and Rick Perry in attacking Romney's record at the private equity firm Bain Capital, opting instead to focus on social issues, electability and the universal health care law Romney signed as governor.

Santorum has been polling in the teens in South Carolina, while Romney has been hovering around 30 percent. Romney also holds a wide leadover Santorum nationally.