I think people are often startled when I, a fairly mild-mannered mostly-establishment guy at heart, suddenly start sounding like a wild-eyed radical when speaking about the social consequences of the concentration of mass media in the hands of a few corporations, many run as personal fiefdoms by hard right figures such as Rupert Murdoch.
I believe that there is a multitude of evidence, however, that right-wing ownership of radio and TV skews content far to the right. And now, alas, we have one more: see Orcinus on what happened at KIRO. Note that KIRO is in Seattle, one of the more liberal towns in America. And it can happen there.