I worked most of the 90s on projects aimed at increasing electoral participation by low income people and I am convinced that just about NO incumbent, of either party, wants the electorate expanded. The existing electorate worked to get them in; why change it? For the Dems, they have seldom been able to deliver much for their low income constituents, so after a few years in office, they especially don't want pushy newcomers questioning whether they've come through for the communities.
it is tough work getting these low income non-voters to vote -- they don't believe anyone is going to help them, so they don't care. We have to create the situation in which communities put expectations of voting on their members. This exists for many older Black folks, but not the younger generation.