Labour candidate Anna Lorck has won the Tukituki electorate by 772 votes from National's Lawrence Yule.
The electorate billed as being the tightest race in Hawke's Bay did not disappoint on election night, with Lorck leading incumbent MP Lawrence Yule all evening by a margin that swung from a peak of 1800 to a trough of 900, before quickly climbing back and settling at around 1400 after 75 per cent of the votes were counted.
As the evening ended, the margin dropped back to 772.
Labour also dominated the party vote - 47.1 per cent - in the traditionally blue electorate.
At about 8.15pm with 34 per cent of the vote counted, and an 1800 margin, Lorck had said she was feeling "overwhelmed at the support."
"We've run an incredibly hard campaign for seven years and it is overwhelming ... this is the accumulation of seven years of hard work."
"It's taken 15 years to turn this seat to Labour, I cannot underestimate the huge swing to Labour and the phenomenal leadership in Jacinda Ardern, it's amazing."
Supporter Mardi Thompson said it was "very exciting" to see all the hard work the "huge" team behind pay off.
Supporter Coco Bullock said Lorck deserved to become the MP.
"She works hard, no one works harder than her and if she becomes MP she will be the best MP Tukituki has ever seen."
Earlier, in the evening at about 7.20 pm when 11.3 per cent of the vote had been counted Yule had said he was feeling "good."
"A lot people voted early, I get that so I'm quietly confident, I think it's going to be a close run thing but you only need to win by one vote and it'll take well into the evening I think."
"The first ones [votes] give an indication but less than half the people voted early according to our stats, half the people voted today so I'm not going to be thinking anything until nearer the end."
Supporter Mick Lester said at 11.3 per cent the votes coming through were likely those who had voted early and that it was "far too early" to determine the final result.
At 24 per cent of the vote counted supporter JJ Singh was still optimistic that Yule would be back for Tukituki as more votes came through.
He said the campaign had been "awesome."
It is the second election the two have gone head-to-head, and the third for Lorck as a candidate.
In 2017, Lorck picked up 15,467 votes compared to Yule's 18,280 - a healthy rise on her 12,047 votes in 2014 against a different candidate.
Both had previously acknowledged the race for the seat would be tight, citing the popularity of Jacinda Ardern and the Labour party this election as a factor.
In the week in the lead up to election night Yule had said he felt "confident" about returning to parliament while Lorck said the race was "exceptionally" tighter this election and she had been having "really positive" conversations with people.
Throughout the campaign Lorck had campaigned on the fact that she was a "local" candidate, living in the Tukituki electorate, as opposed to Yule who lives in Napier.
"It is time that we were represented by a local MP who lives in the electorate," she said on Tuesday.
It was an argument that Yule described as ''completely spurious."
Yule had campaigned on his recent experience in parliament and ability to secure local commitments from National such as the upgrade of Hawke's Bay Hospital, roading upgrades and more recently an upgrade of Cranford Hospice.