I don't think it's fair to describe O'Reilly as having a conservative bias. The useful usage of "bias" around here has roughly been "predictable error". If we had a perfect policy optimizer, we could compare it with O'Reilly and conclude that he systematically overestimates evidence for conservative policies (a conservative bias) or underestimates it (a liberal bias). But conservative supporters of O'Reilly certainly don't currently believe that he exhibits a conservative bias. They just think that he neutrally evaluates policies and rates conservative ones as better because they are in fact better. A battery has a bias for outputting current rather than consuming it, but that doesn't make it bad.