James Dobson endorses Santorum

GREENVILLE, S.C.-- Rick Santorum didn't win presidential dropout Rick Perry's endorsement on Thursday, but he received one from another influential conservative - Focus on the Family founder James Dobson.

The endorsement from Dobson comes a week after Santorum gained the support of more than 150 prominent evangelical leaders, who met in Texas to decide which candidate they would coalesce around as an alternative to front-runner Mitt Romney.

"The institution of the family is the key issue facing this great nation. It is the foundation, the bedrock, upon which every dimension of Western Civilization rests," Dobson said in a statement. "Of all the Republican candidates who are vying for the presidency, former Sen. Santorum is the one who has spoken passionately in every debate about this concern."

Earlier this week, Santorum also picked up the endorsement of Penny Nance, president and CEO of Concerned Women for America, a national anti-abortion organization.

The endorsements from prominent Christian conservatives may give Santorum a boost as he heads into Saturday's primary in South Carolina, particularly as his primary rival for the evangelical voting bloc, Newt Gingrich, deals with the fallout of a televised interview with his ex-wife, Marianne Gingrich, to air tonight on ABC.

In the interview, Marianne Gingrich says her then-husband wanted an "open marriage" as he was carrying on a six-year affair with Callista Gingrich, his current wife. Those details may be less than appetizing to South Carolinian GOP primary voters, 60 percent of whom identify themselves as evangelicals.