The party's platform shifted from moderate economic liberalism to increased emphasis on state interventionism during Robert Muldoon's National government from 1975 to 1984.

In the 2017 general election, despite leaving government, the party secured 44.4 percent of the vote and won 56 seats, making it the largest caucus at the time in the House of Representatives.

However, because of the effects of the Great Depression and a perception that the existing coalition government had handled the situation poorly, the National Political Federation lost heavily in 1935 to the Labour Party, the rise of which had prompted the alliance.

Because of this, perceptions that he remained too much under the control of Coates and his lack of real support from his party colleagues, Hamilton failed to prevent Labour's re-election in 1938.

However, in the 1949 election, thirteen years after the party's foundation, National won power after taking eight seats off Labour, and Holland became prime minister.

Campaigning on an anti-communist platform and exploiting the Labour Opposition's apparent indecisiveness, National returned with an increased majority, gaining 54 parliamentary seats out of 80.

Holyoake, however, had insufficient time to establish himself in the public mind as prime minister, and lost in the election later that year to Labour, then led by Walter Nash.

[22] Within two years, the National Party removed Marshall as its parliamentary leader and replaced him with Robert Muldoon, who had previously served as Minister of Finance.

Bill Birch's "Think Big" initiatives, designed to invest public money in energy self-sufficiency, stand in contrast to the party's contemporary[update] views.

In both the 1978 and 1981 elections, National gained fewer votes than the Labour opposition, but could command a small majority in Parliament because of the then-used First Past the Post electoral system.

However, the party lost some support from Muldoon era policy based conservatives when it continued the economic reforms which had ultimately led to the defeat of the previous Labour government—these policies, started by Labour Party Finance Minister Roger Douglas and popularly known as Rogernomics, centred on the privatisation of state assets and on the removal of tariffs and subsidies.

[citation needed] Many more conservative and centrist National supporters preferred Muldoon's more authoritarian and interventionist policies over the free-market liberalism promoted by Douglas.

[31] At the 1993 election, National was narrowly able to retain government owing partly to a slight economic recovery and the opposition being split between three competing parties.

And, as a result of the new electoral mechanics, the New Zealand First party, led by former National MP and former Cabinet minister Winston Peters, held the balance of power after the 1996 election.

In October 2003 English gave way as leader to Don Brash, a former governor of the Reserve Bank who had joined the National Parliamentary caucus in the 2002 election.

[33] Strong campaigning on a tax-cuts theme in the lead-up to the 2005 election, together with a consolidation of centre-right support, may have contributed to the National Party's winning 48 out of 121 seats in Parliament.

National, however, remained the second-largest party in Parliament (marginally behind Labour, which gained 50 seats), and had fewer options for forming a coalition government.

Before the leadership of John Key, the National Party had made renewed efforts to attract social conservative voters,[citation needed] through adoption of anti-abortion and anti-same-sex marriage policies.

In the 2005 general election run up, it was revealed that the Exclusive Brethren, a conservative Christian group, had distributed attack pamphlets critical of the Labour Party and praising of National to letterboxes throughout New Zealand.

It was later admitted by the leader Don Brash that he indeed did have knowledge of the plan, a statement that was contradicted by MP Gerry Brownlee who subsequently denied the National party had any foreknowledge.

Brash resigned on 23 November 2006, immediately before the release of Nicky Hager's book The Hollow Men, which contained damaging revelations obtained from private emails.

United Future leader Peter Dunne retained his ministerial post outside Cabinet which he had held within the immediately preceding Labour Government.

In response to New Zealand's rising debt, Finance Minister Bill English made budget deficit-reduction his main priority for the first term.

[12] New Zealand First, led by Winston Peters, held the balance of power, and formed a coalition with Labour, who also gained Green Party support, marking an end to the 9-year National government.

[45] Following the Christchurch Mosque shootings, the party removed content from their website which indicated opposition to the UN Migration Compact; a position also espoused by the terrorist in his manifesto.

[20] The party's principles include "loyalty to our country, its democratic principles and our Sovereign as Head of State; recognition of the Treaty of Waitangi as the founding document of New Zealand; national and personal security; equal citizenship and equal opportunity; individual freedom and choice; personal responsibility; competitive enterprise and rewards for achievement; limited government; strong families and caring communities; sustainable development of our environment.

"[67] National supports a limited welfare state but says that work, merit, innovation and personal initiative must be encouraged to reduce unemployment and boost economic growth.

[69] The last major interventionist policy was Prime Minister Robert Muldoon's massive infrastructure projects designed to ensure New Zealand's energy independence after the 1973 oil shock, Think Big.

[75] The National Party's core base has traditionally comprised European New Zealanders (Pākehā), social conservatives and rural voters,[76] although it targets other groups too.

National traditionally had a strongly decentralised organisation, designed to allow electorates and the five regions to appeal to the unique voter base in their area.