Yesterday we reported CNN political contributor Roland Martin will be filling in for eight weeks while Campbell Brown goes on maternity leave in April. But can Martin, who supported Barack Obama during the presidential election and also both Bushes during their presidential runs, continue the "No Bias, No Bull" mantra of CNN at 8pmET?

Yesterday, in a story about February ratings, network president Jon Klein told the AP, "Look at Campbell Brown's show. It is all about delivering the dose of common sense and clear thinking that is necessary for a time like this, and we don't mean clear thinking as a euphemism for our way of thinking or ideology."

After the news about Martin's appointment yesterday, Politico's Michael Calderone wrote about a CNN staffer who, "said a couple weeks back that they didn't expect Martin because he's regarded as a partisan, while Brown's show is billed as a non-partisan alternative to her 8pm competitors, Keith Olbermann and Bill O'Reilly."

A CNN spokesperson put it this way to TVNewser: "Can Roland Martin — who has been a journalist for 20 years and has supported both democrats and republicans — offer common sense and a broad range of opinions when he subs for Campbell for a couple of months? Yes — watch the show in April."