Transcript for Chris Christie Explains His Fat Jokes on Letterman
New jersey governor, chris christie, is now making big headlines for candid talks about his health and his weight. Is it all part of his ramp-up for a possible presidential run? Abc's dan harris has been tracking all of that. Reporter: Good morning. Chris christie is coy about whether he's running for president in 2016. But he's taking some very public steps to deal with what, fairly or not, could be a major campaign issue. It was a brilliant sight gag. Chris christie, sitting across from david letterman, who has lampooned the governor for his weight. And pulling out a doughnut. I didn't know this was going to be that long. Reporter: But making clear he takes this issue seriously. Of course, I care about it. And I'm making the best effort i can. Sometimes I'm successful. And other times I'm not. And sometimes per of great success are followed by periods of great failure. Reporter: The spectacle of a male politician repeatedly having to address his looks, the way hillary clinton dealt with talk of her different hairstyles and pantsuits. And sarah palin with questions over her post-baby weight loss, strikes some observers fascinating. The fact that a man has to deal with questions of his appearance, is a real sign of the times. Even a man who is a governor of Reporter: Connie mariano, who helped president clinton lose 30 pounds in office, said she cringed when she saw christie eating that doughnut. Somebody of that size, i would assume they have issues regarding blood pressure and blood sugar. That's high risk for stroke and heart attack. Reporter: Christie says his own doctor has warned him, too. So far, up to 50 years old, I've been remarkably healthy. And my doctor continues to warn me that my luck will run out soon. Reporter: And he insists he has a plan to deal with it. There is a plan. Whether it will be successful or not, you'll all be able to notice. He doesn't mince words. There's a way that his size could play to his advantage. If he's able to take some of the weight off and keep it off, he'll have a great relatable story to tell on the campaign trail. That worked for mike huckabee running for president. If he wants to run, he has to lose some real weight. He'll have to lay off the doughnuts. He may. But this was a good way to take some of the pressure off. Humor, as you know, george, humor is a great way. No question about it.
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