Obama hits back

White House hopeful Barack Obama has hit back over a television advertisement, which questions his readiness to lead the United States.



Republican John McCain\'s campaign reportedly released the advertisement, which juxtaposes images of Obama with those of American celebrities Britney Spears and Paris Hilton.



Titled ‘Celeb’, the ad calls Obama the biggest celebrity in the world, but questions his economic policies.



The Democrat has responded by accusing his rival of negative campaigning, and of only revealing what he was against.



The Republicans have been keen to stress their belief that Obama is too out of touch with the public.