How many Republicans does it take to fill up a comedy club? Twelve: One to concentrate on the show and 11 to fend off all the reporters asking them how it feels to be a Republican with a sense of humor. At least, that's what it looked like Monday night at the Laugh Factory in Times Square, where three conservative comics were promising an evening of GOP comedy. This sounded every bit as appealing as an evening of lefty comics promising an evening of Abu Ghraib thigh-slappers. Which perhaps explains the low turnout. But humor is - by definition -...