Nah. Trump's gotten all the Republicans he's going to get. Most of those Sanders voters will vote for Hillary. Look for her to get six or seven point bump out of her convention and she will never trail.
I agree that Trump is tapped out. Hillary can easily gain the Bernie supporters by just offering the VP position to him (or to Warren, with Bernie in the cabinet).
And her SuperPAC can air ads to persuade disaffected GOP members that she'd be better than Trump. /as well as remind everyone about his statements (to seal up the Hispanic vote).
The thing is, to Democrats, Hillary is like Romney... a candidate they don't want, but who they can hold their nose and vote for.
Trump is a candidate that about 20-25% of the GOP cannot vote for, even holding their nose.
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