The same conditioning that the Bill O'reilly fans have to spew hate and venom at Democrats... Bill himself conditions those fans to do so.
That's WHY some of us are supporting Obama. He's not trying to achieve power by directing hatred and venom... conditioning those that listen to him to refuse to listen to others... He's talking about getting us as a nation to learn to listen to one another without shouting and hating each other again.
We want that.
But 27 years of conditioning, from both sides, to attack with venom rather than logical debate is a very difficult thing to overcome. Especially when confronted by one of the more hateful figures that has been preaching hate and confrontation against us for many years.
Still, most of the crowd was quite civil, and I daresay more civil then had O'rielly or the Limbaugh crashed a Clinton or Edwards campaign stop... and I'm certain had someone like Sharpton (the democratic foil to O'rielly and Limbagh) crashed a Romney or a McCain event he would have been treated far worse... Though I believe Huckabee is genuinely trying to cross the boundaries as well, so I think that scenario would have been similar.
The point is we don't understand civil disagreement anymore... we've been conditioned for something more similar to civil war. So when someone like Obama tries to bring us together, and we WANT him to succeed, you can't expect everyone to immediately act in accordance with Obama's message the day they decide to join the movement. :)
Obama himself treated O'rielly quite civilly, while Bill made a complete ass out of himself and acted like a child. :)