If there is, I have never seen it. Their biggest problem is they simply CANNOT STAND to hear opinions that contradict their own. In spite of their perpetual boasts of being 'liberal' or 'open-minded', they get a case of the vapors whenever they hear something they don't like, and will do whatever they can to silence their opponent.
One common tactic they often use to try to silence someone who expresses a conservative or classical liberal opinion on some political topic is to claim that the opinion is out of place at whatever time or location it is being expressed. Here is an example from a Yahoo group I subscribe to called Hunt-R-ESS. This group is for people like me who hunt with Springer Spaniels.
One of the participants posted a link to a website called "Hunters Against Obama". A fellow named Archie Hendrix responded:
Re: [Hunt-R-ESS] Hunters Against Obama - ENOUGH!!!!!!!!!!!!!!!!
Agreed. There are plenty of us hunters who are for Obama, and who see what eight years of a Republican administration has done to our great nation. But there are far more relevant sites on which to discuss those issues.
Archie is certainly correct that political opinions are irrelevant to a group about Springer Spaniels. But notice how he manages to insert his anti-Republican, pro-Obama opinion into the discussion anyway.
Why are the left so afraid of healthy debate? Could it be because they harbor misgivings about their own beliefs?