Democratic Primaries:
(Unenthusiastic (or "lesser of the evils") votes are in italics)
1960: Wayne Morse
1964: Lyndon B. Johnson
1968: Robert F. Kennedy
1972: Shirley Chisholm
1976: Sargent Shriver
1980: Edward Kennedy
1984: George McGovern
1988: Jesse Jackson
1992: Jerry Brown
1996: Bill Clinton
2000: Bill Bradley
2004: Dennis Kucinich
2008: Dennis Kucinich
Republican Primaries:
(Unenthusiastic (or "lesser of the evils") votes are in italics)
1960: Nelson Rockefeller
1964: Harold Stassen
1968: Harold Stassen
1972: Pete McCloskey
1976: Harold Stassen
1980: Harold Stassen
1984: Harold Stassen
1988: Harold Stassen
1992: Harold Stassen
1996: Harold Stassen
2000: John McCain
2004: Lincoln Chafee
2008: Ron Paul
Chafee was never a candidate for the presidency.
http://en.wikipedia.org/wiki/Write-in_candidate
He didn't even run as a write-in, though. You could write him in, of course, but he still wasn't a candidate, neither as a write-in nor on the ballot.