Given the fact that the DNC just makes up the rules as they go along and they would prefer fascism to socialism, given the options, a Sanders nomination to be the Democratic candidate is a very long shot.  Getting the nomination and then winning the presidency is, for so many reasons, an even longer one.  A Sanders presidency, if he won, would then be violently opposed by the powerful elite and their pawns.  A successful Sanders presidency may, however, be the only thing that could prevent our complete descent into fascism in the US.