Mitt Romney is very wealthy. The Boston Globe pegged his net worth at somewhere between $190 million and $250 million. So it was probably a bad idea for him to respond to a challenge from Texas Gov. Rick Perry at Saturday's GOP debate by offering to wager $10,000—more than a lot of Americans have in their savings accounts right now—that he had never supported a national individual mandate. Here's video, via TPM:
To make matters worse, Romney didn't just give President Obama grist for a campaign ad—he'd also lose the bet. Romney did, at least until recently, believe that his Massachusetts health care plan offered a model for the rest of the country.
Update: On further review, it's not clear whether Romney would lose the bet, since he didn't specifically call for a federal mandate in his (since-revised) book. But Perry's right that Romney supports mandates on principle, and he has, in other forums, endorsed their implementation at the federal level.