Bob Novak is already writing Clinton's post mortem. His theory is that HRC ran too centrist too soon.
This makes some sense. The conventional wisdom is that you need to run to the base in the primaries (hence Democrats run left and GOPers run right) then run to the center for the general. Such a course requires a lot of verbal and intellectual gymnastics, and the person who best does it ends up winning the presidency.
HRC, figuring she was inevitable, skipped the first part and immediately started triangulating. The base it turned out was not as supportive as she expected and she is now paying the price.