The Labour Party leadership election of 1963 was caused following the sudden death of Labour Prime Minister Hugh Gaitskell.
Immediately following Gaitskell's death Brown assumed the office of Prime Minister, much to the annoyance of many cabinet colleagues and indeed the majority of the labour party.
Pundits predicted a two horse race between Wilson and Brown, with a close result.
The candidates were:
- George Brown - Deputy Prime Minister (1960 - 1970)
- Harold Wilson - Chancellor (1959 - 1963)
- James Callaghan - Colonial Secretary
Callaghan was eliminated from the contest, but tactically declined to tell his supporters whether to vote for Wilson or Brown. As a result they divided roughly evenly between Brown and Wilson, and were able to give Wilson a majority on the second ballot.