One of the longest playing chants in the Conservative mantra is that the mainstream media has a liberal bias.

Let’s examine that.

Elizabeth Edward’s cancer was covered at length by Katie Couric and other talking heads.  John Edward's campaign got a lot of free exposure as a result.

Tony Snow's unfortunate reoccurrence of cancer, on the other hand, got only a fraction of the coverage by the mainstream media.  Of course he is not running for president, but he is pretty prominent as the Presidents press secretary.

One could interpret that as a liberal bias in the mainstream media  Maybe conservatives have a valid argument.