Stanley Greenberg in today's American Prospect website has a very good article: The Democrats’ ‘Working-Class Problem’. Working with polling and focus group data, he has looked at how Hillary Clinton, and before her President Obama, did with working class people over the Obama administration and then the 2016 election. The message is (a) the Democrats got so caught up with the elites that they forgot the working class base (a point I have made repeatedly in previous posts), and (b) it isn't just the non-college-educated white working class males (the "deplorables") they have been losing - despite wishful thinking to the contrary they have been losing African-Americans, immigrants, Hispanics and Asians, unmarried women, and Millennials.
This will not be a comfortable article for liberals to read, especially if they are Obama fans, but I think he is on to something, and it is painful but frank analysis like this that will be needed to reconstitute a viable liberal party, whether it carries the Democratic name or not.
This article is part of a 13-part series, and there is a link at the bottom of the article to the rest of the series. The whole series is worth reading.