Trump really knows how to seize advantage of a weakness.
And remember, he's already primed the pump.
He's labeled Clinton as "crooked" and "lacking stamina" far before all this happened. He must have seen something, cause everything she's done since then has confirmed it.
Granted, the primaries remedy this to an extent, except when you have the unabashed stacking that was employed to counter recent 2012 and 2016 primary campaigns.
Democracy is at its most interactive in the early stages of the election, but the vast majority of people will never leverage that opportunity. People don't act until a media apparatus cues them to cast a vote for its packaged candidate de jour.
He has been successful in business and is now at the helm of one of the most powerful political parties in the known universe. No one has that kind of "luck". There is something more there.