It's understandable how McCain wouldn't vote for Bush. After all Karl Rove and the Bush campaign had a number of smears against McCain.
My personal favorite?
“McCain may be unstable as a result of being tortured while a prisoner of war in North Vietnam.”
This from the people who have made torture the new American way.
Of course, the point of the article at HuffPo is that the McCain who couldn't stomach voting for Bush in 2000 is now embracing him (even though his approval numbers are at an all time low) so desperate is he to become president. Just another example of Flapjack Johnny flipping once again.