After almost 28 years in politics, Bill English will give his valedictory speech on March 1.
Five contenders have confirmed their bid to replace him as National's leader, with deputy Paula Bennett indicating she'd like to keep her role.
"National hasn't had a leadership contest like this for more than a decade," says Newshub Nation panelist and Stuff political editor Tracy Watkins. "If they get it wrong it could haunt them in opposition for years.
Years in Parliament: 9
Former portfolios include: Labour, Transport, Communications, Economic Development
Current position: Shadow Leader of the House, Spokesperson for Economic & Regional Development, Spokesperson for Immigration
Pitching himself as the 'generational change' the National Party needs, Simon Bridges has policy chops, comparative youth and strong appeal to the conservative caucus. He would be National's first Māori leader and is experienced, affable and ambitious. He has also proven himself in Opposition, forcing a fledgling government onto the back foot over a technicality during Parliament's opening day this year. Being a conservative male might count against him however, as caucus contemplates who can best counter Jacindamania in 2020.
Years in Parliament: 15
Former portfolios include: ACC, Justice, Corrections, Police
Current position: Spokesperson for Transport, Spokesperson for Revenue
Judith 'Crusher' Collins has the most experience of all the candidates running and would undoubtedly be a firm hand in opposition. But, while her forceful personality could be an effective foil to Ms Ardern's stardust, her ability to unite the National Party behind her and to win the public vote in 2020 is in question. Numerous scandals during her long tenure, including the Oravida incident, pushed John Key to place her on final warning in 2014. Her campaign so far is doubling down on her ruthless image, tweeting last week that she 'stabs from the front', along with the hashtag #stronganddecisive.
Years in Parliament: 9
Former portfolios include: Internal Affairs, Communications and Information Technology, Associate Minister for Canterbury Earthquake Recovery, Justice, Courts, Social Housing, Social Investment, Housing New Zealand, Associate Finance Minister
Current position: Spokesperson for Justice, Spokesperson for Workplace Relations and Safety including Pike River
Occupying a mid-ground between the iron lady of Judith Collins and the self-styled 'compassionate conservative' Simon Bridges, Amy Adams is pitching herself as the 'progressive' candidate for a modern National. Ms Adams made a strong showing of party unity when she announced her candidacy, with four MPs, including Nikki Kaye and Chris Bishop, flanking her in support. Positioning herself as the perfect blend of rural and urban, Ms Adams is economically conservative but socially liberal, giving her broad appeal within the caucus and across the nation. However, her non-confrontational approach to the leadership race might be overshadowed by Ms Collins' bolder tactics.
Background: Police Officer, Private Security Contractor
Years in Parliament: 6
Former Portfolios include: Statistics, Land Information, Defence
Current Position: Spokesperson for Defence
A relatively unknown quantity, Mark Mitchell has the lowest profile of the five candidates. A former Police officer, hostage negotiator and police dog handler, he also ran a private security company in the Middle East before his entry into politics. While his outsider status may work in his favour for those sick of establishment politics, he will have to work fast to build the recognition and support already afforded to the likes of Ms Collins and Mr Joyce.
Background: Media mogul
Years in Parliament: 10
Former Portfolios include: Transport, ICT, Finance Minister, Tertiary Education, Skills and Employment, Science and Innovation
Current Position: Spokesperson for Finance, Infrastructure
Steven Joyce is pitching himself as the pragmatic choice for leader, saying he is "a strong advocate for New Zealand, someone who can get things done". Mr Joyce has one of the most recognisable names in politics and claims support from "right across the country, within the caucus and without." While he is doubtlessly an experienced contender - second only to Ms Collins - whether he has the mass appeal to match Ms Ardern in the popular vote in 2020 is questionable. Also questionable is whether he will be dogged by running last year's election campaign which failed to get National back into power.
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