The wear and tear that usually plagues third-term governments is not yet showing for the National-led one, a political analyst says.
It has been a year since National won its third term, and the party remains ahead in the polls.
Colin James' four-poll rolling average puts National at 47.4 percent, slightly above its 2014 election result. Labour and the Green Party combined sit at 43.3 percent, 4.1 percent behind National.
"If you take the last two periods of third-term governments, the opposition party was comfortably ahead, in one case a long way ahead, and that's definitely not the case right now," said Mr James.
He put that down to a range of factors.
"I think it's a mix of the appeal of the prime minister - it's still quite strong, a reasonably well-functioning economy, although that's now coming off the boil...
"And an opposition that isn't together and hasn't really sorted itself out yet but is starting to make some progress."
Prime Minister John Key was probably worth "about five percentage points" to the National Party polling, he said.
"He is an unusual character. He seems to be able to shrug off any criticism and still appeal to a very wide range of people."
Labour and the Greens had work to do if they were going to have a chance of winning in the 2017 election, he said.
"If [they] can start looking like an alternative government then I think we might see quite a different picture in 12 months."
But National also faced some challenges, including a drop in economic confidence, he said.