Why are liberals wanting CNN to fire Lou Dobbs while staying silent about Carolyn Maloney?

I don't know anyone who wants Lou Dobbs to be fired. CNN has a reason to keep him on the air and it has more to do with pleasing an audience that wants everything told in their perspective. Imagine cutting him off from the air, those same people would accuse CNN of showing liberal bias (though they don't have any commentary shows that display liberal views)