Why are conservatives so much better at glib rhetoric than liberals?

This is a big assumption, I know, and anyone who can support it or refute it should make their case. However, it is my perception that conservatives are doing something much better than liberals when it comes to media.

Rush Limbaugh and Glen Beck and many others have been able to make big livings for years by telling lies and making fun of liberals. Liberals don’t seem to be able to lie back at them and make any money. Air America was a grand experiment that went bankrupt.

Conservatives, it seems to me, have no compunction about using dishonest rhetorical tricks in order to make others look stupid. For example, they are great at setting up straw men to bash, when the straw man has nothing to do with their opponent’s point of view.

People like Limbaugh, and before him, William Buckley, are great at inviting a guest in to talk about one thing and then sandbagging them with another topic altogether—a topic the guest knows nothing about. The host then succeeds at making the guest like an idiot, and by extension, all that they stand for must be stupid.

Why don’t liberals do this shit successfully?