NEW JERSEY - Forget the health care fight and forget Sarah Palin.
To put it in non-PC terms, the most intriguing question in American politics is this: can a fat man be elected governor of a major state?
In New Jersey the incumbent Democratic governor, Jon Corzine, is trailing the Republican Chris Christie. Or rather Corzine was trailing, until he started running a highly controversial advertisement against his well-built opponent.
The ad ostensibly takes aim at how Christie allegedly pulled strings to escape some traffic violations. But the real message is even more personal.
The camera lingers on Christie's ample girth as he manoeuvres himself out of an SUV. Just in case viewers didn't twig, the voice-over accuses the Republican of "throwing his weight about" to obtain these favours.
Not surprisingly, the Republicans are furious, and ordinary voters profess to be shocked by such base tactics. But the campaign seems to be having an effect.
The contest is starting to tighten, and when focus groups are asked to describe Christie, increasingly the first adjective to be heard is "fat".
That is not good news for the candidate. Fatness, psychologists say, conveys the impression of a lack of discipline and self-control.
And fatness is a stigma.
But one fat man who became a success story is Mike Huckabee, who weighed 136kg when he was governor of Arkansas. Then he was diagnosed with diabetes at the age of 48.
Huckabee not only shed 54.4kg and wrote a best-selling book. He also gave John McCain a run for his money for last year's Republican nomination and is an early front-runner for 2012. Chris Christie could yet be on to a good thing.