The video: In a "shameless" new attack ad (watch below), Newt Gingrich dredges up an old story — first reported by the Boston Globe in 2007 — that paints GOP presidential frontrunner Mitt Romney as a cold-hearted animal abuser. When the Romney family took a 12-hour road trip to Canada back in 1983, the story goes, their station wagon was so stuffed with sons and suitcases that Mitt decided to cart the family dog, Seamus, in a crate strapped to the roof of the car. En route, one of the Romney boys noticed a brown liquid dripping down the rear window, what the Globe described as "payback from an Irish setter who'd been riding on the roof in the wind for hours." Romney calmly pulled into a service station, hosed off the car and dog, placed the dog back on the roof, and continued. Gingrich's ad "For The Dogs" recounts these events, closing with Romney cheerfully explaining to Fox News' Chris Wallace that the dog was happier in his "completely airtight kennel" than he would have been in the crowded car. The ad then cuts to a title card reading "Imagine what Obama would do with a candidate like that."

The reaction:
It's unclear whom this ad damages the most. I'd pick Newt, says Tommy Christopher at Mediaite. "For a candidate who has tried to make a distinction between 'going negative' and drawing legitimate contrasts, this is an exceedingly cheap exercise." Still, this story could really hurt Romney, says Rachel Maddow on her show, further defining him as "cold," "unfeeling," and "out of touch." And what disturbs me most, says Neil Swidey, the journalist who broke the story in 2007, in a Boston Globe piece this week, is not the fact that Romney put his dog on the roof — things were different in 1983 — but that he put a clearly sick dog back on the roof. This story fascinates people because "Romney remains an enigma" and Americans are hungry for "flashes of unscripted behavior, whether that involves clumsy conversations with voters or the ham-fisted handling of a distressed dog half a lifetime ago." See for yourself: