How long ago was this? I only started watching when he moved to HBO, but I wouldn't be surprised if at some specific point he liked a particular right winger more than the liberals on that episode - he's been hot and heavy with Anne Coulter more than once. But remember that this is the guy who was fired from ABC for making a statement that was deemed not patriotic enough. He's plenty willing on specific issues to take on the liberals, but he sides with them for the most part.
His show is good, but not worth getting HBO for. However, his show combined with the Sopranos, the Wire, Carnivale, Six Feet Under, and reruns of Mr. Show are.