Yet, remember that period of time after the conventions, but before the first debate? The poll numbers started to even out. Trump faded into the background somewhat, while Clinton's emails, pneumonia, etc. took center stage in the media world. So let's pose a question: can the media help Trump's campaign by asserting that the reopened FBI investigation will help Trump's campaign?
The question rests on the observation that a great deal of media attention focuses, not on policy substance because, well, who gives a shit about that? Instead, most attention, particularly towards the end of the campaign, focuses on the horse race aspect of the campaign. Who is ahead, and who is behind? Of course, that is precisely what I do, but then, I'm an elections-focused political scientist. I'm not a journalist, and I do not accept any responsibility to inform anybody about anything beyond my own narrow interests. Besides, if you are reading this, you have probably at least met me anyway.
The general press, however, find themselves in a different position. With a presidential election that has gone on for just under four years (yes, Clinton started campaigning right around Obama's second inauguration), they have pretty much done the policy thing already. The extended campaign makes it virtually impossible for the media to stay focused on policy. Eventually, they just shift to the horse race.
At that point, though, they are left asking questions like whether or not Comey has helped Trump and hurt Clinton. In fact, they can do little else in this case since they have no information about what was on the Abedin/Weiner computer (aside from what we really don't want to know). The question itself, though, has the potential to create a self-fulfilling prophesy. It is intrinsically negative coverage for Clinton to focus on such questions. Whether it is enough to give the presidency to Trump or not is another matter, but the fact that we are stuck in the horse race coverage phase of the campaign puts us in self-fulfilling prophesy territory.
By the way, I'm getting my theoretical material from a mostly outdated book by Tom Patterson called Out of Order. It would be really nice if he would write an updated version for the new media environment since his basic theoretical framework for the media is still the right one. And, outdated or not, his old book is still worth a read.