I must disagree with your statement, and suggest you read this poster's comment...
http://www.democraticunderground.com/discuss/duboard.php?az=view_all&address=132x4348320#4348776'gist: Were Obama to be successfully branded as "the black candidate", he would begin to be grouped with "the black candidates" of yesteryear... Jackson, Sharpton... and his credibility as a politician with a wider base would be diminished, affecting the voting in later primaries. Obama has a LOT to lose by having the media begin to project him as "the black candidate."