Before the election, the National Party governed with 47 seats, a small majority. The opposition Labour Party held 43 seats, and the Social Credit Party held two. Although National theoretically commanded a two-seat lead over the other parties, dissent within the National caucus (particularly by Marilyn Waring and Mike Minogue) resulted in serious problems for National leader Robert Muldoon.
The 1984 election was called when Marilyn Waring told Muldoon that she would not support his government in the vote over an opposition-sponsored anti-nuclear bill. Muldoon, visibly drunk, announced a snap election on national television. There is debate over whether the election was necessary — Waring had not threatened to block confidence and supply, meaning that the government could still have continued on even if it had lost the anti-nuclear vote. Nevertheless, Muldoon appears to have wanted an election to reinforce his mandate (just as Sidney Holland sought and won a mandate to oppose striking dock-workers with the 1951 snap election).
Muldoon’s government, which had been growing increasingly unpopular in its third term, was seen as rigid, inflexible, and increasingly unresponsive to public concerns. The Labour Party had actually gained a plurality of the vote in the previous two elections, but had narrowly missed out on getting a majority of the seats. Labour’s primary campaign message was one of change — Muldoon’s government, which employed wage and price controls in an attempt to “guide” the economy, was widely blamed for poor economic performance. Labour also campaigned to reduce government borrowing.
The New Zealand Party, founded by property tycoon Bob Jones, was launched primarily to oppose the Muldoon government (although it did not support Labour). A right-wing liberal party, it promoted less government control over markets, in contrast to the paternalist and somewhat authoritarian policies of National, the other significant right-wing party.