I believe that Colon Powell was asked by Mr. Bush to be SOS in his administration Colon did what a lot of Military men do. When your president calls you answer. Even if you do not expressly agree with your president.
I would have considered a McCain vote if he had not gone to crazy base-ville to get votes. He could have had a good solid 60% vote if he had take the center 60% and left the fringe left and radical right out of the equation. He was a maverick because it was moderate on many issues.
I know that with our primary system it is nearly impossilble for a true moderate candidate to win the primaries and that is a shame.