Before today, May 17, I didn't think Hillary. Clinton as the Democratic nominee would have trouble attracting Sanders primary voters.
Now I do. I am really struck by the Clinton campaign responded to the flap over the Nevada convention brouhaha. Their campaign flat-out won there. They got what they wanted. And her nomination is all but certain at this point.
So why pick now to write off the Sanders campaign as violent rabble? I find it hard to believe that this isn't a signal to everyone that Clinton has no intention of making any special appeal to Sanders supporters. I think it's very likely they've decided that they don't need to, that they don't even want Sanders to campaign for the Democratic ticket and that there will be no special effort to turn out younger, new voters in November.
It looks like they are going on the assumption that Trump will be such a weak candidate that At Least She's Not A Republican will be more than enough.