National MP Steven Joyce has confirmed he is considering running for the leadership and expects to make a final decision in the next few days.
Joyce told the Herald he was talking to other National MPs and supporters about the leadership "and considering my position".
"My motive is to ensure the best team is in place to beat the Labour Government in 2020 rather than personal ambition.
"The biggest focus is to stop the Government implementing the kind of policies that will damage New Zealand."
Judith Collins and Simon Bridges have confirmed they will contest the leadership, which the caucus will vote on in a fortnight. Amy Adams is expected to join that list later today.
Others who have said they are considering a bid are Mark Mitchell and Jonathan Coleman. Paula Bennett has ruled out a leadership tilt, but wants to stay on as deputy – meaning somebody will have to challenge her if they want that job. Nikki Kaye has ruled out both positions.
Joyce was Finance Minister when Bill English was Prime Minister and in former Prime Minister John Key's inner circle. He entered Parliament in 2008 and was appointed directly into Cabinet.
He has led National's election campaigns since 2005, reforming the party and its campaign machinery.
Joyce was derided by some for his claim of an $11.7 billion hole in Labour's books during the campaign but has never directly said he was wrong.
He filled in for English at Waitangi this year.
Joyce's influence has frustrated some in National and he has been blamed in some quarters for the failure of National to get back into Government after talks with NZ First leader Winston Peters.
But others credit him for National's ongoing high polling and discipline.