Don’t worry, you don’t vote in NJ. For the GOP in NJ, I can only compare him to Governor Whitman (the one who was whining about how the Repubs were too far right/conservative); the taxpayers here overwhelmingly support him (while the usual suspects from the left oppose him), and that used to mean something on Free Republic.
If Christie is allowed by the media to be the Republican candidate, it would only be because they know he’d get crushed in a landslide. As he likes to point out himself, he represents the people of NJ, and I’ll point out that he does it better than any I recall in my lifetime.
You’re right that he always says he just wants to do his job as governor, but in the next sentence, when he’s inevitably asked if he has presidential ambitions, he always says, “Look, I don’t know where I’ll be in a few years.” In other words, yes.