Strangely enough, Paul's strongest area according to PPP was upstate.
Paul's been doing well with working-class and low-income voters, which I assume describes upstate.
THE COMMON WORKING MAN SUPPORTS RON PAUL
more seriously, his base this time around is a bit different. Besides his default support bases (the youth, indies, anti-war, etc) he benefits somewhat from gun voters, survivalists, and people from more rural areas (as was the case in New Hampshire, where he actually won Coos but performed worst in Rockingham). He's been pushing his religious cred, and its working to some degree.
Also, this is somewhat off topic, but has anyone noticed that according to CNN Paul gets 15% of the national primary, but 19% in the "South"? I can't think of any southern state that Paul does better than average in that would boost his numbers like that (Kentucky maybe, Louisiana if they were able to predict turnout I guess).