"Establishment" politicians of both the GOP and the Democratic Party are doing badly this year. Hillary Clinton is as Establishment as they get.
It could be in her case that the Clinton coalition is no more. It could not get Al Gore elected. Kerry did worse in trying to resuscitate it. Obama got clobbered by margins larger than 10% in five states (Arkansas, Kentucky, Louisiana, Tennessee, and West Virginia that Clinton won) -- twice. Democrats have a better chance of winning Virginia (a state that neither Carter nor Clinton carried) than any of the New Orleans-Charleston (WV) arc.
At this point I practically see Hillary Clinton losing much like Kerry in 2004 -- but Bernie Sanders winning much like Obama in 2008 or 2012.
You are absolutely correct, either the Dems lose a 272-266 style election, and Sanders win a 2012 map, the email drama, voters are sick of cynical, not Dem politcs.