After serving four terms in the House of Representatives , he ran for the Senate in 1988 , where he lost in the primary ; and in 1990 , where he was defeated by Democratic incumbent J. James Exon by a 59 % -41 % margin .
After serving four terms in the House of Representatives , he ran for the Senate in 1988 , where he lost in the primary . 
 He ran again in 1990 , and was defeated by Democratic incumbent J. James Exon by a 59 % -41 % margin .