Both Labour and National start the election year with partner problems.
National's problem is that we don't know who their partners are - or whether they will have any. There's quite a list of possibles: the Maori Party, United, Act, the Conservative Party, New Zealand First. But they are only possibles.
The ones signed up with National may not make it to Parliament and those who do may not run with National.
National could very easily trounce Labour in the polls but lack the numbers to form a government. The out-polled Labour Party may well form a government because it does have a support party.
Labour's partner problem is the opposite of National's: voters know only too well their potential partner. The Greens consistently poll more than one vote for every three that Labour pulls. That means by the logic of democracy the Greens making up a quarter of any Labour-led government with ministers, parliamentary roles, policy and decision-making.