Not sure if I understand what the OP DUmmie is saying, but Err America failed long before there was anti-Obama sentiment. Progressive talk radio fails because Progessivism is an illusion and the more it is discussed, the more obvious it becomes.
We had a liberal station here and right now the only liberal hosts on it are Sly in the morning (a local area lib) and the Allen Colmes show at night. In between it carries two hours of Glenn Beck, three hours of Dennis Miller, a couple of hours of radio for drunk Wisconsinites, and a couple of hours of Dr. Drew Pinski (sp?). Oh, and late night they have Laura Ingraham.