I don't think a nation with a white racial majority (72 percent mind you) would vote for a black president simply because he's black. That isn't how humans work. Also, old people. But the opposition to gay marriage and racism abroad is quite literally dying out with the Baby Boomers.

It's more like the Republicans lost the votes of the young, gays and women, as well as minorities. And they know this, which is why the GOP is currently turning itself inside out with all of the complete 180s that it's doing on various topics that it initially opposed.