I just stumbled across an interesting read by the Time Magazine that talks about the 5 major mistakes Clinton made that have moved here basically to the brink of defeat from what at the start really seemed like a walk in the park towards clinching the nomination.
The Five Mistakes Clinton Made - TIME
Overall I'd say they got it nailed there. I find the anectode about her chief strategist (Penn) rather disturbing to tell you the truth though, lol.