In the first place, I think that it is people who are not thoughtful who do the demonization.  I have encountered many among those who are considered liberals who bend over backwards to understand those on the other side.  Thoughtful conservatives are just that -- thoughtful -- they do not demonize.  I believe that much of the demonization comes from those who have money and power and who do not want those who lack power to cooperate with each other.