This article is pretty stupid, really, overthiniking these topics by several degrees. Really, shows like The Daily Show, while they do draw a more liberal than conservative viewership, are not "liberal" shows, and they go after the inanity of both parties with equal glee. However, these days, the right is just producing a lot more facepalm moments.
If the right wants their own satire, it is already present in these shows. Their politicians just need to clean up their acts a bit and quit saying and doing so many stupid things. Not their policies, but rather how they campaign and lobby to advance them. Then the jokes will be distributed more equally between the left and the right...
This is why the right wing attempts at these shows fail, because they put the politics ahead of the inanity of the situations being mocked, where the so-called "liberal" shows just mock first and never really worry about where their jokes are landing on the political scale.
As for talk radio, there may be more to this. I think liberal do tend to get tired of the format and would rather have more factual reporting a la NPR than hours of discussion around facts that devolve into nothing more than meaningless partisan spin.
But another factor to consider on that front is that, for decades now, talk radio has been used as a major means of message delivery for the right, and has tremendous fininacial support from the right, while the rich and powerful on the left pretty much left Air America to wither and die.
Fox News, while successful in the ratings now, never would have made it if it were not for Murdoch's money and his ability to attach the network to the very established Fox name.
Why There's No Conservative Jon Stewart - The Atlantic: "A unified theory of why political satire is biased toward, and talk radio is biased against, liberals in America."