In September 1997, Neumann announced his candidacy for the United States Senate against Russell Feingold. Both candidates had similar views on the budget surplus, although Neumann was for banning partial-birth abortion while Feingold was against a ban. Both candidates limited themselves to $3.8 million in campaign spending ($1 for every citizen of Wisconsin), although outside groups spent more than $2 million on Neumann; Feingold refused to have outside groups spend their own 'soft money' on his behalf. Feingold defeated Neumann by a slim 2% margin in the election. According to the Milwaukee Journal-Sentinel, Neumann had a 30,000 vote margin outside Milwaukee County, but was overwhelmed by a 68,000 vote margin in Milwaukee County.