A rather ridiculous meme I have been seeing lately on social media is hardcore Bernie Sanders supporters saying Democrats lost the election because they nominated Hillary Clinton instead of Sanders. They would have us believe that Bernie Sanders could have beaten Donald Trump. Personally, I don't believe Sanders could have won. I think he would have been beaten worse than Clinton (and probably would have lost even the popular vote).
Kurt Eichenwald has written an excellent article for Newsweek on myths that some liberal Democrats believe. I have reposted here the part of that article dealing with whether Sanders could have won.