In New Jersey, any candidate for high office can count on getting smeared over taxes, corruption, the economy, or all of the above. But in this fall's hard-fought gubernatorial race, an unlikely issue has popped up amidst the usual mud-slinging: the portly physique of Republican challenger Chris Christie. Ever since Jon Corzine released his now-infamous attack ad, in which a disdainful voiceover claims Christie improperly "threw his weight around" as a U.S.