Anoraks answered
1952 is the answer if one is talking simply about the Presidential general election - ie. once the parties have picked their candidates - but my question referred to the "presidential race". In 1952 President Truman actually contested the New Hampshire primary and announced his retirement after losing badly to Estes Kefauver (though Adlai Stevenson was eventually the Democrat nominee that year).
(Incidentally, the 1952 Democrat nomination was also contested by Jeffrey Archer's half-brother-in-law, the Connecticut senator Brien McMahon, but that's another, quite fascinating, story.)
The real answer is 1928 - 80 years ago - when neither the sitting President, Calvin Coolidge, nor his Vice President Charles Dawes, contested any part of the election.
For record, President Hoover was beaten in 1932, President Roosevelt won in 1936, 1940 and 1944, and Truman won in 1948.
After 1952, President Eisenhower fought in 1956; Vice President Nixon in 1960; President Johnson in 1964; Vice President Humphrey in 1968; President Nixon in 1972; President Ford in 1976; President Carter in 1980; President Reagan in 1984; Vice President Bush in 1988; President Bush in 1992; President Clinton in 1996; Vice President Gore in 2000 and President George W Bush in 2004.
I'm Michael Crick, and I'm Newsnight's political editor. My guiding rule is that in any story there's usually something the politicians would prefer the world not to know. My job is to find that out.
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