The latest campaign song tearing up the Internet has one important difference from its predecessors, at least in my mind: It's actually good. This one is "Black President," by rapper Nas. As Time's Ana Marie Cox observes, it's not "as twee -- or as fully positive -- as the will.i.am video[s]" but the lack of syrupy sweetness is certainly a good thing. If you're not a rap fan, you might not like this, but if you are, it's fairly classic Nas.
One interesting thing about this for those who might not otherwise get the reference -- the sample that gets repeated a lot throughout the song, "Although it seems heaven-sent, we ain't ready to see a black president," is from "Changes," a song by Tupac Shakur that's also very political but decidedly less optimistic. Seems like a deliberate reversal of the message, even though, as Cox noted, Nas' song isn't entirely positive either.
The only embeddable version of the song I've found is below, but it's just a preview -- if you want to listen to the full song, it's here.