Conservatives.

“If it were true that conservatives (not necessarily tories meant here, ed.) were racist, sexist, homophobic, fascist, stupid, inflexible, angry, and self-righteous, shouldn’t their arguments be easy to deconstruct? Someone who is making a point out of anger, ideology, inflexibility, or resentment would presumably construct a flimsy argument. So why can’t the argument itself be dismembered rather than the speaker’s personal style or hidden motives? Why the evasions?” – Ann Coulter
Yet the left virtually always move directly to ad hominem arguments without even passing Go!