1. - Jason Robards Jr, The Night They Raided Minsky's, 1968. Better choice for Norman Wisdom's music-hall comedy partner than Robards.
2. - Roy Scheider, All That Jazz, 1979. Scheider’s biographer Diane Kachmar said his other rivals for Joe Gideon (aka Bob Fosse) were: Alan Alda, Alan Bates, Warren Beatty, Robert Blake, Elliott Gould, Jack Lemmon, George Segal, Jon Voight.
3. - Robert Vaughn, Superman III, 1983.
4. - Martin Sheen, The West Wing, TV, 1999-2005. One of two actors considered for President Jed Bartlet. He eventually joined the series as Presidential candidate Arnold Vinick, his fourth screen US senator. (Alda almost ran for the Senate in 1995).