From another thread:
The next Democratic coalition is here, and it is the predominant feature of the contemporary American landscape. The next few decades are going to be very difficult for the Republicans, a la the 1930s through 1960s.
The Democrats have created a winning coalition of minorities, younger/better educated whites, and unmarried women. Like all coalitions, it will eventually lose ground or break up. Say the GOP is ascendant sometime in the next 20-40 years. What does their coalition look like?
One possibility for the GOP is that they would peel off parts of the Democratic coalition, since single women, African Americans, Hispanics, gays, secular voters, environmentalists, unions, young people and the educated upper-middle class have different, sometimes contradictory, priorities.
The Republican base is currently married white people. So, that would be one way to make inroads into other ethnic groups.