I think what this study is really measuring is the degree to which the tight parameters of acceptable political debate…parameters which are enforced by the country’s political punditry…end up convincing the main consumers of political media that the country is more right-wing than it is. In other words, since most people don’t consume much political media, most people aren’t pulled all that far to the right by political media.
Put it this way. If you are inclined to support universal health care or same-sex marriage, but you don’t watch cable news or reads newspapers or listen to talk radio, your opinions aren’t likely to change. But if you do consume those sources of information, your view of health policy and (until very recently) same-sex marriage will be deemed extreme, out of the mainstream, unserious, or even radical. And seeing your ideas portrayed that way is likely to lead you to change you opinions.
So, what happens?
Politicians consume a lot of political media, while their constituents do not. Over time, politicians come to believe that their constituents are considerably more conservative than they really are.
Anecdotally, I can confirm that when I talk politics with people who are not strong consumers of political media, they tend to offer up policy prescriptions that are not even part of the conversation in Washington DC. Most often, this is because their prescriptions are crazy or unworkable or impossible in the present political climate. But sometimes it is because people who don’t tune in haven’t had their imagination destroyed like the rest of us.