This new district Grayson is running to win is the 9th district. The 3rd district which carries the statistics you are showing is not part of this race. Barak did also win the 9th district area in 2008 but they were mostly hispanic votes. You have just chosen the wrong Florida district to profile.
Grayson’s race is in Central Florida. The district you are describing would be huge from Kissimmee to Gainesville to Jacksonville is many hundreds of miles in distance. District 9 is not that big. It goes from South Orange County through Osecola County and part of Lake County.
This map with the overlay of the congressional districts on the state should help.
You can plainly see that district 3 is in North Florida and district 9, the right district, is in Central Florida. It is a major hispanic district and not a black district at all.
Thanks for the info, Wary!