Kevin Drum, along with others, have put in their two cents worth to explain the results of this study by Media Matters. The upshot of the study is that conservative, syndicated columnists outnumber liberal, syndicated columnists at every type of of newspaper, big or small, urban or rural, liberal or conservative. One thing that might add to the explanation that I haven't seen mentioned. Although my views have always been distinctly left of center, when I was younger (in the '70s and '80s, before so much of the major media became crap) I always preferred to read the conservative columnists, George Will, Jack Kilpatrick, William Buckley and the like, as doing so helped to sharpen my own arguments. The conservative arguments were never persuasive to me, but they certainly helped make my own arguments better. I had, and have, an attitude that is particularly suited to the scientific disciplines, and the reality based community, in which one is constantly looking for ways to test one's beliefs and arguments. It seems to me that this point of view is particularly common among liberals and progressives, so it may well be that both sides of the isle have a strong desire to see writers on the right, but only left leaning readers want left leaning writers.