Why Does Bill O'reilly pretend to be " Independent"?

I decided to turn on O'reilly tonight, While having dinner with my girlfriend we watched. Over the course of I'd say about, 10 minutes. We counted O'reilly Said " Some People on the left are anti american", and other similar statements like that, " Alot of people on the left are anti-american", " To many Anti American People on the left", we noticed he never mentioned any anti american people in the middle or on the right. Then he starts demonizing " ObamaCare", The starts demonizing Rahm Emmaunal , then starts demonizing Planned Parenthood. Then some other Liberal websites. Well, If he' is indy, why does he spend his entire show attacking the left wing? I mean I don't have an issue with attacking the left, but when does he ever say anything about anyone on the right? He never mentioned anything bad about any right wing website, or any rightwinger, or right wing organization. So Basicly does he just say he's indy? And attack the left all day? How does that work?