Ever since the Nixon debacle, journalists have appended the third syllable of the name of the prominent hotel to other words to denote a political scandal. Thus we have Bridgegate, the upset created when it came to light that members of the Christie administration intentionally closed lanes on the George Washington Bridge to snarl traffic in Fort Lee, because its Democratic mayor would not endorse Republican Christie for a second term as Governor. Christie had denied that there had been any political motive behind the lane closings, and now the big question is whether he actually did not know his appointees were doing this, or whether he is covering up his involvement.
Of course, the lesson of Watergate is do not become involved in a coverup, because the press will find the truth; and we need only go back as far as Gary Hart to learn that lesson. Christie's immediate disavowal of any involvement by his administration comes across as that of someone who so trusts his people that he finds the idea ridiculous; had he any inkling it might be so, or even that it might appear so, the politically prudent response would have been to say that these were indeed serious charges and that he would immediately open an investigation into them. We can accuse him of trust misplaced, but then, we all have to trust someone or we revert to primitivism, hunting and preparing our own food.
The other question, though, is how this impacts his election prospects. Some of that depends on how the matter unfolds over the coming weeks, and whether the now independent investigation is satisfied that he was not involved, did not approve or have knowledge before the fact. Of course, if he expressed frustration or disappointment at some point (like asking whether no one "will rid me of this turbulent priest") it might be that someone took him seriously, and that investigators cannot discount the possibility that they were correct in taking it so. It will require more than merely plausible deniability to eliminate the issue entirely; and we can be fairly certain that his Republican rivals for the nomination will attempt to keep the issue alive as long as it favors them to do so, and if they manage to damage his credibility sufficiently to cost him the presidency, they will undoubtedly say that in retrospect it is obvious he was the wrong candidate. After all, politicians are a breed that eats their wounded.
On the other hand, if he comes out of this clean he can certainly rebuild his popularity; he still holds majority favorable ratings in this state early in his second term despite the problem. In the CPAC straw poll for Republican Presidential nominee, he listed fourth (behind strong leader Rand Paul at 31%, Ted Cruz at 11%, and Ben Carson at 9%) with 8% of the strongly conservative group's vote. Teapot Dome this is not, and this far in advance of the election it will become one of those problems of the past before we know it. After all, the plagiarism scandal that knocked Delaware Senator Joe Biden out of the Presidential primary race in 1987 apparently did not disqualify him from becoming Vice President in 2008 (although some will argue that he is part of an administration that values effective lying). There are enough scandals to touch everyone in politics right now, and we can be pretty sure that when the mudslinging starts in earnest, Christie will be far from the dirtiest participant in the fight.