Newt and Rubio. The Republicans will never get the black vote but Rubio could really help with the Spanish vote. Cain will be Sec of State. Give hell to the internationalists.
Rubio would get the Cuban-American vote in Florida - but probably not the Hispanic votes nationally.
Newt is too politically flighty for the top seat. He is brilliant but politically erratic. He a good doer, he is a lousy leader.
Newt lacks the core leadership principles and vision any good leader must have. Newt is really good at identifying solutions to existing problems, he really bad at seeing what the real problems are.
Do you want a leader or a manager? Cain leads, Newt manages. For the top slots you want leaders, not managers.