This makes total sense. It really does. There are a lot of black people in SC. The last name "Greene" with the "e" on the end evidently is a surname commonly seen among black people. This is no stranger than if an Italian person voted for someone named Tony Soprano, knowing it would be an Italian.
Rawl is just flipped out because he lost. Evidently despite all his money and campaigning he didn't spend enough time ensuring the black people knew who he was. Big mistake. Or maybe they did know and don't want him in office. Tough luck Rawl. Get over yourself; you lost.
In Chicago so many people automatically vote for an Irish name that candidates have been known to change their name. The judicial ballot is especially tedious to go through. A couple of elections ago, a woman whose married name was not Irish but whose maiden name was legally changed her name to show both her maiden name and her married name and was duly elected.