It's actually a point that hurts Sanders now these days and that many hate him for: Clinton would have won the election if Sanders (unwillingly, I must add) wouldn't have moved so many voters to rather not vote or to even vote for Trump in protest for what the DNC did to him. There are quite a few who won't forgive him for ruining an election that was promised to the democrats.
No really, that is something I see not even a hint for. I see it only ever used as a strategy to smear Sanders. Because, maybe there were a few Bernie or Bust people, but would they have voted for Clinton in the first place? I think it is the other way around: that Sanders fought hard in the primary activated many voters that would have been passive otherwise because they had long given up on voting, as they felt neither party would do anything for them. Sanders could actually bring them back in the political process. That some of these people were in the end disappointed that Clinton was the nominee and didn't show up on election day is meaningless, as they would have been absent if Sanders wouldn't have been in the primary in the first place. But many of the people he activated in the end voted for Clinton.
In the end Clinton got 65 million votes, just about the same as Obama did. To be precise, Obama got 65,915,795 votes 2012, while Clinton got 65,853,514. So she lost about 62K voters, pretty much nothing compared to one of the most beloved presidents. Trump on the other hand got 62,984,828 votes, about 2 million more than Romneys 60,933,504. So in the end Clinton did not lose because she lost voters, Trump won because he convinced voters. In which way he did that is a miracle to me, but he did.
So, people want to tell me, that Clinton - a candidate with certainly a lot of problems and baggage - would have magically gotten more votes than Obama, if not the mean kid Sanders threw a wrench in it? Yeah no, I don't buy that. It is obviously bull to damage Sanders, and it disheartens me that so many people believe that bull.