Actually, the key player behind of lot of these conservative commentators on TV is a guy named Roger Ailes, a sort of conservative/Republican media hitman who's been working the media since Nixon. He's the one who got Rush Limbaugh on TV, and he's the one who basically put together the commentator team on Fox New for Rupert Murdoch, and now essentially runs the place. Here's the URL to a bio of the guy (somewhat slanted, but a good chronology), and you can see how much one guy with no scruples and a lot of money behind him can do in America.
http://home.earthlink.net/~zkkatz/page86.html