I've noticed recently that many of my conservative friends spend a lot of time disavowing beliefs commonly associated with the extremes of their party--creationism, Obama birthplace conspiracies, and the gold standard being particularly common examples. I've noticed, however, that though these ideas are pretty clearly wrong if you care to look at "facts" or "the world" or "logic" they tend to enjoy support from fairly prominent Republicans. Sarah Palin is a creationist. Ron Paul is all about the gold standard, and despite the release and vetting of every form of birth certificate known to man, Obama's birthplace is still treated as suspect by many Republican lawmakers.
In the interest of balance, I was trying to figure out what the extremist ideas on the liberal side of the spectrum were, and who was giving them voice. But I can't find anything even close to comparable. Is this my bias, or are Dem's just more grounded in reality?