New Jersey Gov. Chris Christie reacts to a repeated question during a news conference after he announced that he has chosen Jamie Fox, a former top aide to Democratic Gov. Jim McGreevey, to be New Jersey's new transportation commissioner. (AP Photo/Mel Evans)

Late Thursday night, WNBC -- the NBC affiliate in New York City -- reported that a federal investigation into the closure of lanes on the George Washington Bridge had turned up no link to New Jersey Gov. Chris Christie.  The nine-month investigation has "thus far uncovered no evidence indicating that he either knew in advance or directed the closure of traffic lanes on the span," according to the report, which cited federal officials.

That's very good news for Christie and his potential 2016 presidential prospects. (A caveat: This is one report -- albeit it from a very credible organization.  But federal officials have no commented on the report yet.)  Here's why.

While Bridgegate has not been a hot topic in the political world for some months, Christie has, without question, been damaged by it. And, until Thursday night, he lacked any defense other than his insistence that he had not been involved.

So, every time he met with grassroots activists in early 2016 states or potential campaign staffers or, most importantly, major donors, Christie never had a full-proof answer to just how much trouble Bridgegate might be for him. Now, again assuming the WNBC report is accurate, Christie has an absolute trump card to play in those conversations.  He can now say some version of this: "I didn't know about it. No clue.  But don't take my word for it.  The feds looked into it for NINE MONTHS and they reached the same conclusion." That's a far more compelling argument than the one he had when he woke up on Thursday morning.  In an interview with a local radio station Thursday night, Christie said that he was "not surprised but you're always grateful to hear that, you know, the things that I said appear like they're going to be confirmed if these reports are accurate."

Now, Christie's exoneration from involvement in Bridgegate doesn't mean that it will go away.  As I mentioned above, it has already robbed him of the two most precious things for a presidential candidate at this stage of the race: buzz and momentum.  And, even if Christie did nothing wrong, his cluelessness about the political retribution two of his top aides were exacting will be worrisome to plenty of Republican donors and voters. Add to all of that the major hits the state's credit ratings have taken under Christie and you can see there is plenty of work that he still needs to do.

But, for the first time in a long time, Christie can at least see a plausible path back to the top tier of a Republican presidential primary. He remains the most naturally gifted communicator in the potential field and, assuming that Bridgegate is truly behind him, the person with the best relationships with the Wall Street major donor crowd that helps provide the financial backbone to presidential candidates. Now, with the dark cloud of the looming investigation seemingly gone, those traits have a far better chance of shining through.