The third theory is that Christie's obesity effectively ruled him out, and his recent hospitalising asthma attack would spook health-fanatical Americans too much. "Look, I'm sorry," wrote Bloomberg's Michael Kinsley, "but New Jersey Governor Chris Christie cannot be president: he is just too fat." Headlines such as "Is Christie Fit to Run for President?" clearly riled the governor in a way that the late-night comedians did not, and he finally snapped, saying: "To say because you are overweight you are undisciplined — I don't think undisciplined people get to achieve great positions in our society — that kind of stuff is just ignorant. The people who wrote it are ignorant people. What they do is they further stigmatise people in a way that is really irrelevant to people's ability to do a particular job." Of course he's right, and William Howard Taft left the White House weighing over 300 lbs, but in a country where both fanatical jogging and morbid obesity are rife, Christie's weight was bound to be an issue. (Of course in electoral terms, if he managed to snaffle the vote of every overweight American, he would more than counter Obama's present tally of 92 per cent of black Americans.) 

The fourth theory bandied about to explain his decision not to run is that his family were apparently adamantly opposed to it. Chris and Mary Pat Foster were college sweethearts who studied at the University of Delaware together, and married aged 24. They have four children between the ages of eight and 18. What few people appreciate about the delightful but formidable Mary Pat Christie is that she is easily as politically savvy as he is, and was just as active in the college Republican society when they were undergraduates. At the dinners of senior Republicans, media moguls, elder statesmen and Fortune 500 company CEOs that I've attended, her opinion on politics is almost as eagerly sought as his. They can finish each other's sentences. Occasionally wives do stop their husbands running for president — Alma Powell is credited with opposing Colin's candidacy, for example, and Governor Mitch Daniels of Indiana is thought to have bowed to family pressure not to run — but if Mary Christie was adamantly opposed to her husband's bid, it would have been for sound political, rather than namby-pamby personal reasons. 

The last theory is that Christie wouldn't have won the nomination even if he had stood. His stance on the Second Amendment — the right to bear arms — is considerably at odds with that of the conservatives, as he supports stricter enforcement of existing gun laws, and probably new ones too. New Jersey also does not actively prosecute illegal immigrants. Indeed, in 2008, Christie stated publicly: "Being in this country without proper documentation is not a crime." These views might be perfect for winning independent and Hispanic votes in the general election, but they don't resonate at all with the grassroot Republicans who choose the presidential candidate in the primaries. 

So people suggest that Christie flunked the race because he would have been squeezed into the dangerous spot on the  podium to the left of Romney and even Jon Huntsman, a place where all his brains, eloquence and charisma could not have saved him.