Prime Minister John Key says Michael Wood's victory in the Mt Roskill by-election isn't a "great celebration" for the Labour Party.
"No other political party other than Labour showed up," he said.
"The Greens didn't show up. New Zealand First didn't show up and, actually, the voters didn't show up."
"So you've had one of the lowest turn out we've really seen a mainstream by-election.
"I know that Labour will want to say somehow this has been good for them. If it is, this is a pretty low bar for Andrew Little to get over."
Meanwhile, Labour leader Andrew Little says the win is proof that Labour can win a general election, despite poor showings in national polls.
Mr Little says polls "come and go" and voters who have moved away from Labour are there to be persuaded and convinced.
"And as we’ve seen in the local body elections and the Mt Roskill, when people hear a message, hear a clear message, a good message, have good contact with us, then we win their confidence and support," he said.
"And we will go into 2017 with that."
Mr Key says the Mt Roskill seat is a strong Labour seat so he was not expecting win the by-election.
"If Andrew Little think victory is holding a seat they've held for 60 years that's good. But I don't think that makes general election history," said Mr Key.