The Duke phenomenon is interesting. I have relatives who became Duke fans when they moved to North Carolina. It has a lot to do with front-running, status and race.
I'll never forget the Pitt newspaper article prior to the 99 championship advising people on who to root for. Called the UConn kids thugs, and the Duke kids real students.
That Duke team had Elton Brand, Magette, Avery and Burgess on it, all kids who left early and didn't graduate. By comparison, UConn had some upperclassmen in Ricky, Jake V., Rashamel, Rip and Kevin Freeman (sure I'm missing someone). It was totally undeserved, but it's the way people look at Duke and the opposition.
I'd never accuse Duke of "milking" the image but for some fans it plays a part. Just like the Celtics were accused of being racist, I'm sure part of the appeal for some fans was the whiteness of the team. Never mind that the Celtics were the first team with a black head coach and the fist team with an all black starting five. Even black fans of the NBA developed a distaste for them, but it's not like the white starters (Bird, McHale and Ainge) weren't great players.