Cathy, there's always been a connection between folk music and the political left, at least since Woody Guthrie. So it's natural for performers and audience to enjoy that esprit-de-corps at a folk concert, in the same way that GW Bush speaking at a defense contractors' convention grinningly called them "my base." My impression is that conservatives who are inclined toward folk music usually go with country-western/bluegrass instead. It's too bad no one explained that to the Dixie Chicks, but their loss of income is a good indication of the degree of political conservativism in CW fans.

Richard, your folk/art music dichotomy really interests me, since I recently concluded that all the songs I like best, which I think of as folk songs, probably started life as 19th century art songs. And my favorite contemporary song-writer is someone who writes solidly in that art-song tradition, though he sings in a gritty, boozy rock or jazz style (I hate his singing).