Here's a couple of possible answers (at least opinions):
http://townhall.com/columnists/Harry...south_carolina
"Al Greene’s victory in South Carolina has puzzled everyone - Democrats, Republicans, and Independents. When I first heard of the victory of the unemployed veteran, I immediately remarked to my wife that name recognition of the Rev. Al Greene had been a factor. More specifically, it reminded me of a1992 comedy starring Eddie Murphy entitled, “The Distinguished Gentleman.” The movie featured a black con man named Thomas Jefferson Johnson who decided to shorten his name to Jeff Johnson in order to purposely confuse voters into thinking he was a dead congressman."
http://www.themonkeycage.org/2010/06...because_o.html
"And I’m not sure that the potential ballot order effect is implausibly large. Assume for the moment that voters were essentially choosing at random between the candidates. That would imply a 50-50 outcome. The actual outcome was 58-41, which only implies that 8-9% of voters were influenced by ballot margin.
Another question is whether there was any information on the ballot that might have cued voters to choose Greene over Rawl. I wondered whether SC voters might have inferred the candidates’ racial background from the names of the candidates. I looked to see whether there was any relationship between Green’s percent of the vote in each county (data here) and the percent black in that county from the 2000 Census. There is a modest positive relationship, although it is not statistically significant. Ecological inference problems make this analysis suggestive at best, but I don’t see much happening." (Scatter chart below)
Who the heck knows? It's a sorry state of affairs when someone runs for the Senate (essentially) unopposed. Demint is going to return to the Senate, which may or may not be good. There's nothing worse than a one-party state. If there's no political competition, there's no reason for the incumbent to take the people seriously.