CNN, a network known for its regular liberal bias, touted its supposed objectivity versus its competitors in a new ad which premiered on Tuesday evening. The ad graphically associated Fox News with the Republican elephant and MSNBC with the Democratic donkey, and claimed, “If you want to keep them all honest, without playing favorites, the choice is clear: CNN, the worldwide leader in news .” Yahoo! News's Michael Calderone, in his Wednesday article on the new ad , quoted from CNN political director Sam Feist, who claimed that their ad ” simply states the obvious: We're the one cable news channel that doesn't advocate for one political party or the other .” Calderone continued that ” CNN's nonpartisan anchors have struggled against their more opinionated counterparts. Campbell Brown acknowledged her 8 p.m. show's low ratings against Fox News' Bill O'Reilly and MSNBC's Keith Olbermann in her May announcement that she was leaving the network.” [ Video of the ad below the jump ]