The National Party had been in office since the 1960 elections, when it had defeated the short-lived one-term Labour government of Walter Nash. For most of this period, National had been led by Keith Holyoake, whose policies were focused around stability and a "steady as she goes" approach. Holyoake and his cabinet was increasingly perceived as tired and worn-out, so shortly before the 1972 elections Holyoake stood aside for his deputy, Jack Marshall, who took steps to reinvigorate the National Party.
Norman Kirk had been catapulted into leadership of the Labour party at the end of 1965, after 8 years as a back-bencher. He did much to modernise and update the party, but Labour narrowly lost the 1969 election. So Kirk slimmed and dressed to improve his image, and visited several overseas Labour parties to broaden his knowledge. He activated a "spokesman" or shadow cabinet system to spread the responsibility, though it was difficult to avoid one composed largely of Auckland and Christchurch members. But In the Balance wondered (August 1972) whether National could pull off another cliff-hanger victory.
The date for the 1972 elections was 25 November, a Saturday. 1,583,256 people were registered to vote, and there was a turnout of 89.1%. This turnout was slightly higher than the previous election, and considerably higher than the following one. The number of seats being contested was 87, the highest number since the late 19th century.
Norton, Clifford (1988). New Zealand Parliamentary Election Results 1946-1987: Occasional Publications No 1, Department of Political Science. Wellington: Victoria University of Wellington. ISBN0-475-11200-8.
Wilson, James Oakley (1985) [First published in 1913]. New Zealand Parliamentary Record, 1840–1984 (4th ed.). Wellington: V.R. Ward, Govt. Printer. OCLC154283103.