Newshub's latest poll has National on 47.3 percent, polling high enough to form a government alone.
Labour is 10 points behind on 37.8 percent.
With the Greens polling too low to enter Parliament at all, Labour would be unable to form a coalition government.
In a 121-seat Parliament, National would have 61 seats - a majority. It could form a buffering coalition agreement with ACT, who would bring one seat and/or the Māori Party, who would bring two.
National's gain in the polls coincides with the week finance spokesperson Steven Joyce claimed Labour had an $11.7 billion hole in its fiscal plan. It's a claim widely debunked by economists, with National unable to find an economist to back it up.
The poll will be devastating for the Green Party, which continues its downward trend to 4.9 percent.
That's just below the 5 percent threshold required for the Greens to enter Parliament without winning an electoral seat.
When questioned by Newshub, National leader Bill English stuck with his current metaphor of choice - a drag race - saying despite the poll, he believed Labour and National were "level pegging".
"Those numbers are a bit higher than what we're seeing.... What we see is a drag race between the two big parties," he said.
"They are going to be choosing National because we can build on the strength that we have, not slow it all down."
Labour leader Jacinda Ardern said both the Greens and Labour have ruled out an electoral deal to get the Greens over the line.
When asked whether she would rather miss out on power than send a signal for Labour voters to back a Green electoral candidate, Ms Ardern said there has been "real volatility" in the polls and she believed the Greens were polling at a different number.
"Both of us have [ruled out an electoral deal]. We are running our own campaigns locally, and we're campaigning individually for party vote," Ms Ardern told Newshub.
The poll has a margin of error of 3.1 percent and was conducted from September 6 to September 11.