The "niccas in Paris"-scored video shows Hollande campaigning in the outer regions of the Paris metro area, as French voters of various races hold up their electoral cards. It should be noted that Sarkozy has a long history of poor relations with the impoverished Parisian suburbs, where a high percentage of racial minority and immigrant populations live. Hollande is possibly trying to underscore that relationship.
Also, Slate points out that "Creil"-- one of the suburbs Hollande campaigns in during the ad-- is pronounced "cray" as in, "That !! Creil."
Hollande and Sarkozy will face off in the second round of voting on May 6. Watch the ad in question: