Prime Minister John Key is tipping an unhappy new year for Phil Goff, saying the Labour leader is at risk of being rolled after a poll yesterday showed support for him and his party weakening further in recent weeks.

On the other hand support for National and Mr Key has picked up, according to the 3News poll.

The poll found support for National running at 55.5 per cent, an increase of 1.7 percentage points and the party's best showing since February.

Support for Labour fell 1.4 percentage points to 31.2 per cent.

On the preferred Prime Minister measure, Mr Key was at 54.1 per cent against Mr Goff's two point fall to 6.8 per cent - not far above former Prime Minister Helen Clark's 5.3 per cent showing two years after she lost the job to Mr Key.

"I think he's got a real challenge now in front of him," Mr Key told 3News.

"I wouldn't be surprised if the Labour Party caucus decided to roll him in the new year." Mr Key said the stronger support for himself and his party was a great way to go into Christmas.

"And I think it shows you that the public are supporting the direction we're taking the country in."

The poll also found support for the Green Party steady at 7.3 per cent, Winston Peters' NZ First making a small gain to 1.9 per cent, the Maori Party at 1.7 per cent, Act up slightly at 1.3 per cent and United Future at 0.1 per cent.