If Sanders had dropped out of that primary when it was obvious he was not going to win, Hillary would have won the general election. Rabid Sanders fans kept an unrealistic hope he could pull it off until the last minute and then were so heartbroken when he lost that they blamed Hillary and many democrats then would not vote for her. She won the popular vote as it was and certainly would have won the general if there was enough time for the democrats to come together. I think they also figured she would win anyway because who in their right mind would vote for the asshole?