Either Michael Sheen (THE most versatile actor in the world he was first choice for Elizabeth II in 'The Queen' before they gave his role to Helen Mirren instead) or Morgan Freeman.
Yeah, I'm a skinny white guy with red hair, but that last option was just so I could see people's faces drop when the trailer comes out.
EDIT: Damn, I just noticed someone else said Morgan Freeman. Uhm, IDK, Denzel Washington?