Superdelegates hamstrung the process. Kate Brown for instance, the governor of Oregon at the time (who btw was an unelected governer during that term, as her predecessor had stepped down) voted against the will of her constituents for Hilldog -- Oregon had overwhelmingly supported Bernie. Let's not forget some of the caucuses in other states which were outright rigged. An auditorium blew up for Bernie but the presiding party official put it in for Clinton. When shit like that just happens out in the open you have to wonder what's going on behind closed doors.

I believe Republicans actually have a democratic nomination process without superdelegates, which is how they got Trump -- IIRC he had a few early wins and snowballed from there.

There's a number of things going on here, but the short of it is that to become the democratic nominee you need to convince a whole bunch of people, including some super delegates. Hillary Clinton did a better job of this than Bernie Sanders.

How she did it could probably be the subject of an entire book, but no one has ever come up with any particularly scandalous stories about it so far.

Yes, and the superdelegates, whose job was to make sure people didn't pick the wrong candidate (how democratic of them), picked probably the least popular politician in America at the time.

Trump likely would have lost against almost any other candidate, but he had help from the Democratic party, who treated Hil's nom as a coronation.

This is such a silly hill to die on. Hillary clinton won the majority of voters both in the democratic nomination and in the national election.

Yeah she was so popular they had to rig caucuses in her favor, and superdelegates had to defy their constituents.