Chris Christie is screwed.

A quick rundown 

David Wildstein resigned from his appointed (by Chris Christie) position as head of the NJ Port Authority, shortly following the release of prior emails showing his complicity and understanding of the political nature of his involvement in shutting down lanes of the GW Bridge (Bridgegate).  He has now come out and stated that he has evidence that, contrary to what Christie has said in public, Christie knew during the shutdown what was really going on.

The consequences

He's in trouble, as this only fuels the media to go digging for evidence of past bullying and possible malfeasance.  More than that, with Wildstein opening the door to show that Christie knew what was going on, the NJ legislature now has reason to call both Christie and Lt. Gov. Kim Guadagno to testify under oath, as to whether either of them knew what was going on.

I point out Guandagno, because she presents a possible opportunity to play prisoner's dilemma between her and Christie.

If Christie and Guadangno both knew what was going on, regardless of whether they lie or tell the truth to that fact, they may both be impeached and face criminal charges for malfeasance.

If they invoke the Fifth Amendment right to avoid self-incrimination, they will be forced out by public opinion or face an official recall vote.  After all, you cannot pretend to take the high ground on this issue and fire everyone involved, only to invoke the right to avoid incriminating one's self.

But for argument's sake, what if they're telling the truth?  They're scarred from future political office, from not having the interest to address the GW Bridge lane shutdown at the time that it was being conducted.  Remember, Christie received emails requesting that the lanes be reopened, as they were closed without any prior warning -- a violation of the Authority's own policies -- but he ignored them.

White House bid is off

There isn't a scenario where Christie regains his stature and popularity, to make a run for the White House.  The truth is set between Christie allowing the Port Authority to do whatever pleased them regardless of the rules, or that he explicitly knew what was going on, and neither narrative is positive.  So, yes, Christie is screwed.  The bridge closure affected Republicans no less than Democrats or Independents; when they closed the bridge, all voters were turned off.