It has been demonstrated that historically the modern Democratic party platform supports the interests of the masses of people, that is, the poor and the middle class. At this point the Republican party is not really hiding that they are the party of the 1%ers although they use racism to keep a certain segment of the voters voting for them but this will not likely last as even the most ignorant do learn over time because their utility depends on it.
Despite Hillary Clinton's political baggage and lack of appeal as a candidate, she still beat Trump in the popular vote. Even in the key swing states where she faltered due to a poor voter outreach, she was a clear winner in the urban areas of even the swing states. The Republicans benefitted once again from manipulation of the election (2000-hanging chads in Florida + Supreme Court choosing president) and 2016--a close election where the Russians were able to tip the scales for Trump. Time, demography and utility is on our side.