Dan Coats Republican Evan Bayh Democratic The 1998 United States Senate election in Indiana was held November 3, 1998.

Incumbent Republican Senator Dan Coats decided to retire instead of seeking a second full term; he later successfully ran for this seat again in 2010.

Democratic former Governor Evan Bayh won the open seat his father once held.

Bayh won 88 of Indiana's counties compared to 4 for Helmke.