Romney got a pass partly on the virtue of backing away from all his previous policy positions. Christie is a politician, and he might be the kind of guy to do that, but I don't think so.
And of course the other thing was that Romney was the least offensive of a crop of really terrible candidates, and subject to a primary season where the base spent six months desperately searching for some candidate, ANY candidate, who would be a better choice.
Now, that could potentially happen with Christie. But recent history tells us that even 9/11 didn't make Republican primary voters forget Rudy Giuliani's less-than-perfect alignment with party doctrine.
Granted, it's getting to where public opinion can shift a surprising amount in just a few years -- gay rights is one example, acceptance of marijuana is another -- but the Republican Party isn't the most nimble apparatus for dealing with those changes. I expect the leadership is in meltdown mode about now, wishing the Tea Partiers would play ball -- but the Tea Partiers got elected, and in many cases reelected, and as I said I think they're more than willing to go down with the ship over their stupid, evil principles.