Never mind abandoning a political party ... what would make a General turn against a friend of 25 years who had sacrificed so much for this nation -- in favor of a man who just arrived on the scene?  

I believe Colin Powell when he says this decision had nothing to do with race.  Instead, my guess is that it had everything to do with rehabilitating his image with the media (which was tarnished when he became Bush's Secretary of State)...