Bobby "Boris" Pickett, whose dead-on Boris Karloff impression propelled the Halloween anthem "Monster Mash" to the top of the charts while cementing his place as one of pop music's most enduring one-hit wonders, has died of leukemia. He was 69. Pickett, dubbed "The Guy Lombardo of Halloween" for his impossibly catchy No. 1 song, passed away Wednesday night at the West Los Angeles Veterans Hospital, said his longtime manager, Stuart Hersh. His daughter, Nancy, and his sister, Lynda, were at Pickett's bedside. Pickett's multimillion selling single hit the charts three separate times: when it debuted in 1962, again in August...