I think the only good news for Christie is that this happened at a time when nobody is thinking about politics. It might be forgotten by the time the primary season begins. People in New Jersey and New York may still be ticked, but it's not like he's going to win those states anyway. After a while almost every scandal is forgotten. Nobody talks about the IRS scandal anymore and even the NSA scandal is largely forgotten about these days despite Snowden showing his ugly mug every couple of months. And those two were obviously much worse than this.
Honestly though, if he's going to run for president he needs to get better at shielding himself from these scandals. He needs to learn some lessons from Obama, G-Dub and the Clintons.
Actually, I can see Christie using this scandal for his benefit by making it seem like the left is purposely targeting him, especially with the news today about the feds going after him for Sandy Aid. Try to get the right back on his side by playing the victim. Just so as he still appears strong while playing the victim.
Obviously if the scandal leads directly to him then all bets are off though.