From my perspective it's all up to Comey to try and make something out of probably nothing.We know that the AG has already been told to do nothing so is it all going to be up to Comey?
He's going to have reams of jeopardy/testimony against hillary but how does he use it?
If Comey whitewashes the case, then we will learn how corrupt our government is, including the career bureaucrats.
There is one angle that may sound far-fetched, but the Dems including Obama may want to ditch Hillary for Biden. This would be a perfect opportunity to do so without having their fingerprints on it. We know Obama and Jarret hate the Clintons. And they certainly don't want to see them in charge of the Dem party for the next 8 years. Biden would be a compliant Obama surrogate and a protector of his legacy. An indictment would end Clinton's campaign.
The problem will be how to deal with Bernie and his supporters. Bernie will claim he is the rightful nominee, but the Dem Establishment doesn't accept him. The superdelegates will dictate what happens. Obama will be heavily involved to get the nomination for Biden. He will be the "compromise" candidate. To make it more palatable, Elizabeth Warren could be the VP candidate.
The longer it takes the FBI to come to a decision, the easier it is to put Biden in as the replacement. Hillary will have the majority of the delegates and votes, Bernie can't win a contested convention.