Because Ron Paul is as crazy as the proverbial sh*thouse rat. He is a low budget Ross Perot whose continuing presence in the race could put another Clinton in the White House.
One of my Dad's fav-o-rite sayings, "Crazy as an outhouse rat." A couple of others, "Built like a brick outhouse." and "Like a truck load of pigs hittin' a truck load of tin cans."
Oh, and this one, "They won't do anything till people start fallin' over dead in the streets."
LOL.........:}
P.S. Agree that your reply fits, "Like a fist in the eye."