Can't imaging Kerry loosening up enough to do this
Compare and contrast. One of side, we have a president who is comfortable poking fun at himself. On the other, a candidate who is so uptight, he has to proclaim, "I don't fall down. That son of a bitch ran into me," when a member of his Secret Service detail bumped in to him accidentally during Kerry's recent ski trip.
Given the choice, I'd rather have someone who can make (and take) a joke over someone who does sweat the small stuff. But that's just me.