I read/listen to a bit of both (despite living in Denmark), and they strike me as leaning upper-class more than anything else, especially NPR. High culture, art museums and classical music, cultured fancy vacation destinations (Venice! Paris!), that kind of thing. Which all strikes me as more bourgeois than left. The upper classes aren't very culturally conservative, and are embarrassed by reactionary groups with lower-class bases, like UKIP or the Tea Party, so could be grouped on the left if your idea of left is opposing such groups. But they aren't very left economically, and keep their distance from lower-class movements on the left too, anything that gets too "red".
In a Danish context I would imagine the archetypical NPR listener voting for the Social Liberals, who are basically in the exact center (socially liberal, economically free-market, but not radically so in either category).