Zbigniew Brzezinski, one of the most influential foreign-policy experts in the Democratic Party, threw his support behind 's presidential candidacy, saying the Illinois senator has a better global grasp than his chief rival, .
Obama ``recognizes that the challenge is a new face, a new sense of direction, a new definition of America's role in the world,'' Brzezinski said in an interview on Bloomberg Television's ``Political Capital with Al Hunt.''
``Obama is clearly more effective and has the upper hand,'' Brzezinski, who was's national security adviser, said. ``He has a sense of what is historically relevant, and what is needed from the United States in relationship to the world.''
Brzezinski, 79, dismissed the notion that Clinton, 59, a Bloombergsenator and the wife of , is more seasoned than Obama, 46. ``Being a former first lady doesn't prepare you to be president,'' Brzezinski said.