He does not want a vote for not-the-party-nominee to taint his own future presidential aspirations.
Grandaddy, Uncle already had their turns, so it won’t come back on them to vote for Clinton.
He did say several weeks ago that he would vote for Trump, so this really isn’t news.
Sorry, George P. Bush is NOT a natural born Citizen. His mother was a foreign national at the time of his birth in Houston, Texas.