Starring Henry Fonda, Cliff Robertson and Lee Tracy, the film details the seamy political maneuverings behind the nomination of a presidential candidate at their party's national convention.

The supporting cast features Edie Adams, Margaret Leighton, Ann Sothern, Shelley Berman, Gene Raymond and Kevin McCarthy.

In May 1964, former Secretary of State William Russell and Senator Joe Cantwell are the two leading candidates for the presidential nomination of their unnamed political party.

The pragmatic Hockstader prefers Russell, but worries about his indecision and principles; he despises Cantwell for his recklessness but appreciates his toughness and willingness to do whatever it takes.

One of Russell's aides finds Sheldon Bascomb, who served in the military with Cantwell and is willing to link him to homosexual activity he engaged in while stationed in Alaska during World War II.

[3] Bosley Crowther's review of the film in The New York Times cited William R. Ebersol in the role of Governor John Merwin as one of those who "stand out in a cast that is notable for its authenticity".

[5] Ben Cosgrove of Time said, "Considering how ruthless the film is in dissecting the amoral machinations employed in virtually any national political endeavor, The Best Man is remarkable not for its scorn or its misanthropy, but for the even-handedness of its vision.