Time for Clinton to forget about incorporating Bernie's supporters for awhile.
She needs to mount a determined frontal assault and put this thing away, once and for all, so she can turn to the GE full bore. She needs to stop worrying about alienating his supporters. No doubt, some of them will be permanently turned off. They will go sulk on the sideline or vote for some obscure third party alternative out of pique.
That's too bad. But I say let them do it.
I predict that it will be only a tiny minority of Sanders supporters who choose that path. After a little sulking, the grownup Sanders supporters, which I think most will prove to be, will join the fight, rather than sit it out and watch another Democratic President be succeeded by yet another Republican.
Do you realize that we haven't had back to back Democrats Presidents since LBJ won what would have been JFK's second term? And we haven't had democrat elected to succeed a two term democrat since Truman succeeded FDR? That was a LONG time ago. No way any grown up democrats or progressive independents will let this opportunity slip, no matter how hard Hillary takes down Bernie.
So I think Hillary has the right idea of focusing on decisively defeating Bernie now, and worrying about drawing his supporters back into the fray later.
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are critiquing each others' positions and plans, so no doubt she will.
Importantly, though, although the right wing is still holding their character assassins away from Sanders, mainstream media are finally starting to "vet" him. He's mostly gotten a free ride before, but being seen as a serious candidate by winning more delegates has consequences.
That disastrous editorial board interview a couple days ago is already being widely discussed, and it is not the first time he has revealed surprising ignorance of how he would get from the opinions he has held passionately for 50 years to how as president he would enact actual solutions.
Here at new The Atlantic article, "How Much Does Bernie Sanders Know About Policy?" http://www.theatlantic.com/politics/archive/2016/04/bernie-sanderss-rough-ride-with-the-daily-news/476919/
You know, most observers believe Sanders never intended or expected to come this far, so he didn't need actual solutions. For decades he encouraged change mostly as a gadfly criticizing and pointing out problems to others -- experts who themselves would come up with solutions, as he even points out in that interview. I think more than once, like when he mentions the SecTreasury.
Btw, this drawn-out process is frustrating for everyone. 
This is how Clinton loses the primary:
She is in no position to attack Sanders "frontally." Perhaps she is out of better options and almost out of time. Her internal polls must be disastrous for her to take this kamikaze course.
