Are you sure about that? Gore got about 96% of the black vote and Kerry got about 90%. No republican has ever recieved more than 4% of the black vote?
Bush has gained a slight increase in support from African-Americans during his presidency. Although he only got 9% of the black vote in 2000, he received 12% in 2004, with the increased black vote in Ohio giving the victory to Bush over Kerry.Source: Wikipedia