Sanders is (amazingly) a viable candidate.
In a certain sense, "Obamacare" was designed, purpose-built, to bring about full nationalization. It was NOT designed to fail in 2016, but it is failing.
If you think Sanders can't win, you underestimate the desire of people for free (and yes, I mean "free") medical, nursing, and hospital services.
I don't think militant Islam will give Bernie the room he needs to run on free healthcare ("Medicare for all").
But if they do, he can actually win, because he knows what he wants, is transparent, and in some sense the people want it, too.
I do not believe that Sanders would be a viable candidate if not for the fact that Hillary is not such a reviled one.
In any other year a 75 year old Socialist Senator from a relatively small nearly entirely white state would have no chance at winning even the Democrat nomination.
Sure at least 47% of the electorate will vote for more free government handouts but they can get that from Hillary.