NPR reports that almost 38 million people listen to all NPR programming combined. NPR represents the biggest piece of liberal radio in America by far. Sure there are a few others out there, but liberal talk radio doesn't work because the numbers show that minorities gravitate to other types of radio and minorities make up a majority of the liberal base.

While NPR has a big audience, nobody thinks they play a major role in leading the Democratic party. Liberal talk radio just isn't a factor. 91% of the daily broadcast talk radio is conservative, according to the Center for American Progress.

At the same time that liberal talk has had trouble getting off the ground, conservative talk radio has remade the Republican party. It's leading hosts have a seat at the power table in the GOP for sure. Limbaugh and Hannity have the ear of the president and are a big reason he was elected.

As Variety points out, the second largest media market in the US, which Obama won 69% to 29% over Romney, doesn't have a single liberal talk show. It does, however, have Rush, Sean and the other regulars. The problem isn't that there are a lack of liberals in America, it's that they don't want to listen to liberal talk. Instead, they prefer comedy and satire shows where liberalism comes out, but is cloaked in jokes, sarcasm or personal attacks. Liberals prefer their politics a little more cloaked in entertainment.

It's hard to pin down numbers for radio, but I will try using the estimates you can find online. If you add all conservatives up against all the NPR and liberal talkers in the top twenty, you get the following. 88 million listen to conservative talk out of the top twenty talk radio shows. That increases to nearly 102 million if you add financial talk show Dave Ramsey, who clearly leans conservative. 45 million listen to NPR or liberal talk radio among the top twenty talk shows.