 " Treehouse of Horror VII " is the first episode of The Simpsons ' eighth season . It originally aired on the Fox network in the United States on October 27 , 1996 . In this seventh annual " Treehouse of Horror " episode , Bart discovers his long @-@ lost twin , Lisa grows a colony of small beings , and Kang and Kodos impersonate Bill Clinton and Bob Dole in order to win the 1996 Presidential election . It was written by Ken Keeler , Dan Greaney , and David S. Cohen , and directed by Mike B. Anderson . Phil Hartman provided the voice of Clinton . 
