Jim Gardner, played by Harry J. Lennix, is the fictional White House Chief of Staff on the political television drama Commander in Chief. Gardner is the Chief of Staff of independent President Mackenzie Allen. Harry Joseph Lennix (born November 16, 1965 in Chicago, Illinois) is an American actor. ... It has been suggested that Assistant to the President of the United States be merged into this article or section. ... Commander in Chief is a television drama focusing on the presidential administration and family of Mackenzie Allen (portrayed by Geena Davis), the first female President of the United States(Higly unlikely), who ascends to the role after the previous chief executive, Teddy Bridges (played by Will Lyman), dies in office... Geena Davis as President Mackenzie Allen In the television show Commander in Chief, a political drama aired by ABC, Mackenzie Spencer Allen, played by Geena Davis, is the first female President of the United States. ...