Republican presidential candidates Newt Gingrich speaks as Mitt Romney, listens during the CBS News/National Journal foreign policy debate at the Benjamin Johnson Arena, Saturday, Nov. 12, 2011 in Spartanburg, S.C. (AP Photo/Richard Shiro) (RICHARD SHIRO/AP)

Mitt Romney is up with a new ad that takes a not-so-subtle swipe at Newt Gingrich. Called “Leader,” the 30-second ad set to go up on the air in New Hampshire and Iowa this week, features old home video footage of Romney, his wife and his kids, with a voiceover of the former governor of Massachusetts saying:

“If I’m President of the United States, I will be true to my family, to my faith, and to our country, and I will never apologize for the United States of America.”

With images of Romney as a dad and as a husband front and center, the obvious contrast is with Gingrich, who has been married three times and has admitted to infidelity. The ad is the most personal look at Romney and his family life so far as he tries to make more of a connection with voters, particularly social conservatives, who still have concerns about Gingrich.

The ad features close-ups of Ann Romney taking care of the couple’s children, and the camera lingers on her in one shot, as the Republican candidate says that he’s been “married to the same woman” for 42 years.

It’s hard to imagine that Gingrich could make a similar ad.

While Gingrich has framed his personal life as a sort of “Saul-to-Paul” conversion narrative, it isn’t clear whether that will be enough to convince evangelical voters that he shares their values.

But perhaps, with this clear shot across the bow, Gingrich could cut an ad in response where he says, in essence, he hasn’t always been a perfect man, wrap in his faith and weave a narrative about redemption, which could resonate with Christian voters.