I can see the argument for a Clinton-Obama ticket. If she wins, a substantial part of his constituency walks. And there's no one else who could plausibly attract them but Obama -- his appeal is singular. The question is whether he'd want to be on the ticket, or whether he'd worry about being tarnished by a Clinton loss to McCain, worry that joining with Clinton would turn off his fans and make him look like just another grasping politician, and worry that he'll lose his luster if he's forced into her candidacy. But an Obama-Clinton ticket makes no sense. She is not the only Democratic politician with a connection to working class white voters. Moreover, she steps on his central narratives of unity and transformation. I think he probably has to pick a woman -- or at least would be wise to pick a woman -- but Clinton does him harm without doing him much good. And does he really think he can control an operation as brash and overbearing as hers? Will Mark Penn really defer to David Axelrod? Will Bill Clinton? I have my doubts.