In that primary the charts from day one included superdelegates for Hillary and the DNC absolutely put their thumb on the scale in a major way. That primary was an absolutely awful mistake and turned a lot of voters off of the democratic ticket.
Were it not for the bullshit Hillary pulled we likely never would have had Trump as a president - the margin of his election was thin enough that not trampling over the progressive side of the party would have kept him out of office.