The vast majority of Bernie supporters didn't register just for this election. They've been in the party for years. That's what I meant when I said it's always been there. They just needed a champion. He shifted the focus within the party. It's a good thing.
Those who truly supported him can either stick with him today & trust his judgement or whine about being cheated & oppressed as if that actually happened. It didn't.
It may have been with the electorate who are registered democrats but it apparently is not a majority of them (even if it is a sizable minority).
However, it is no longer part of a segment of the elected officials who are democrats. Just look at the number of them who supported whom in the primary.
It's more nuanced than you portray. Those who supported him will have to vote for Clinton if they live in a swing state, there is no denying that unless they've gone insane and fail to recognize the danger of a Trump administration. Those who live in a solid red state where Clinton is not going to win in any case should vote for Jill Stein. Those who live in a solid Blue state where Clinton will win should seriously consider voting for Jill Stein.
Depending on where you live has an impact on whether or not Senator Sanders advice and voting for Clinton is the best course.
The ideal outcome in this election, imho, is Senator Clinton winning by electoral votes with a significant number of individual votes going to the Green party candidate which would put the democratic blue-dogs on notice not to shift too far right on economic issues despite Clinton's victory....
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