Your choice of president?

A few days ago CNN (Showbiz) ran a poll asking people which of the following celebrities they would vote for to become president:

Angelina Jolie (white female)
George Clooney (white male)
Oprah Winfrey (black female)
Will Smith (black male)

The winner was George Clooney. I was excited at first, I love George Clooney as an actor and deeply admire his work with Darfur. But then I thought to myself, this is interesting, both Angelina Jolie and Oprah Winfrey have done some serious humanitarian work and Will Smith has been active through the Will and Jada Smith Family Foundation. In fact, Angelina and Oprah have done as much humanitarian work as George Clooney has. Is there a pattern of the white male being voted as the most preferred person for president? Again, interesting!