Sanders has no chance because he keeps losing in primaries. There is a big difference between showing up at rallies and actually going to vote. I think this is what his supporters seem to forget or are perhaps ignorant of in the first place. Just because you shout loudly and get on tv does not mean you are effecting change.
If Clinton is indicted, or otherwise manages to shoot herself in the foot somehow, Bernie is poised to take the nomination. Especially if he clinches California along with several of the final primary states. Clinton is foolish to refuse a final debate with Sanders, and is foolhardy to dismiss the last of the primary voters as unimportant. Whether you support Bernie or not, it's not very wise of her to dismiss Independent voters as unimportant and to ignore the last of the primary voters this way.
Bernie Sanders does not have a chance for the Democratic nomination. He is garnering a lot of support, but Hillary Clinton needs just a handful of delegates to sew it up. Mathematically, his chances to take the nomination are just not going to happen. Clinton needs to win just 8% of the remaining delegates, an easy feat.
Crowd support at rallies is a terrible metric to determine if a candidate has a chance. Bernie is too far behind with too little election to go to make a difference now. He hasn't had a realistic chance to win for months. His pivoting regarding the superdelegates this election cycle is shameful, as now he wants them to vote against the primary result.