I think you need to look at demographics. And you're right... rich people don't need welfare and social programs, necessarily, but I'd say a fair number believe that societies are measured by how we care for our sickest, poorest and oldest, Bill Gates and Donald Trump among them. Anyone who doesn't believe government should make our moral choices for us is going to vote dem. Poor people don't vote because they don't think it makes a difference for the most part and don't think they are part of the political process. What's true today is what was true during Thomas Jefferson's time.. .it takes a strong middle class for democracy to work.