Namesakes
American First Ladies:
1 first lady
Dolley Madison 1809-1817 
American Presidents:
1 president
James Madison 1809-1817
Fictional Characters from Television:
1 character
Cody Madison 1989 Baywatch
Notable Actors and Entertainers:
2 actors
Guy Madison 1922-1996
Mikey Madison 1999-
Olympic Medalists:
2 gold
(gold) Helene Madison 1932 swimming - 100 m freestyle; swimming - 400 m freestyle; swimming - 4x100 m freestyle relay
(gold) Tianna Bartoletta (a.k.a. Madison) 2012; 2016 4x100 m relay; long jump