Matt Yglesias looks at some charts from Lee Drutman and sees our post-racial future:
I used to hold to the view that the growing non-white share of the electorate would, over time, tip elections to Democrats. I now think the system will remain near equilibrium and what we'll instead see is white voters growing more Republican as Democrats are more and more seen as the party of non-whites. Mississippi and Arizona, after all, have very large minority votes but they're hardly hotbeds of liberalism. Instead they're hotbeds of very conservative white people. This does mean, however, that politics will become even more abstracted away from “the issues” and questions of identity will become even more central.
I'd add that our conception of who is "white" will largely change as well, becoming more inclusive, much as it did in the decades following World War II when Jews, Irish, and Italians were integrated into the fold. So many of the people and votes we're putting in the "nonwhite" column today will be in the "white column" 20 years from now. I'm guessing that a non-trivial number of Democratic votes will probably come from future constituencies who, as today with nonwhites, gays, and Muslims, share common ground largely because of Republican hostility toward them.