Garrison Keillor rambles a bit about radio in the current The Nation, but he drops a few lines that would be out of place on Prairie Home Companion:

The reason you find an army of right-wingers ratcheting on the radio and so few liberals is simple: Republicans are in need of affirmation, they don’t feel comfortable in America and they crave listening to people who think like them. Liberals actually enjoy living in a free society; tuning in to hear an echo is not our idea of a good time. I go to church on Sunday morning to be among the like-minded, and we all say the Nicene Creed together and assume nobody has his fingers crossed, but when it comes to radio, I prefer oddity and crankiness.

. . .

I don’t worry about the right-wingers on AM radio. They are talking to an audience that is stuck in rush-hour traffic, in whom road rage is mounting, and the talk shows divert their rage from the road to the liberal conspiracy against America. Instead of ramming your rear bumper, they get mad at Harry Reid. Yes, the wingers do harm, but the worst damage is done to their own followers, who are cheated of the sort of genuine experience that enables people to grow up.