It is not just about running candidates. Your party has to define itself as the party of the poor people first as the number one priority. As long as the national party is defining itself on social issues and such forth you can run Zell Miller and still lose in WV and similar places.
No, running as the party of poor people is the worst possible strategy. Nobody likes poor people or want to be associated with them. The Democrats need to position themselves as the party of the "middle class."
Then you don't say poor, you say working class.