I find it amusing when people still hold up Christie as potentially being able to win a presidential election. Even before this scandal, Christie had no chance of winning. You can't take his popularity in New Jersey and extrapolate that to the whole country. Christie is hamstrung by his lack of debating skills and his thin skin. He has never had to endure a real campaign or the kind of close scrutiny that a national campaign brings. You can fantasize all you want but Christie is not equal to the task. Is it possible that someone could give him a crash course in public presentation and debate? Perhaps it's vaguely possible but it doesn't fit with Christie's personality. In fact, Christie's over-confidence is his main attraction to Republican voters.
But now you do have scandals and half of his staff is gone and this is only over the bridge. You also have the commercial which seemed to be a campaign ad paid for with public money. He might very well have to pay that back. You have an investigation into the relief money disbursement with clear evidence that he did ignore towns with mayors he didn't like. Then you have his own relief fund and he'll probably end up having to account for that. Then you have his interference with a criminal case for a friend of his.
Christie was hoping to stall the investigation until the subpoena power of the committee expired. He gave his two hour rambling no-information speech as a last-ditch smoke screen to get him past the deadline because he was certain the the new, Republican speaker of the house would not authorize more subpoena authority. But, that didn't happen, the speaker is not quashing this. You have two state investigations, a civil action, and a federal investigation. The only way this wouldn't turn up something is if Christie were completely innocent and we all know that is not the case.
Suggesting that Christie can weather this is a bit naive. Christie is a walking corpse whether he realizes or not. There is no question of running for the presidency, there is no question of running for the senate, there is no question of retaining his governorship. The only real question for Christie is if he will serve jail time and if he will be disbarred. Maybe there is a job for him on Fox.