National MP Andrew Bayly has won the seat of Port Waikato in the by-election by a landslide.
"I feel pretty humbled. It's a great privilege to represent Port Waikato again and something I really enjoy doing. I'm looking forward to continuing in that role."
The electorate which covers the Manukau Heads down to Te Kauwhata was considered a safe National seat.
Bayly received 14,023 votes and more than doubled his 2020 margin of 4313 to 11,245 on Saturday.
"It's a fantastic result and I think people realise they needed to get out and vote. I've worked hard over the last few years and I think that's a recognition of that as well, but I just feel incredibly privileged to be able to represent these good people."
New Zealand First candidate Casey Costello, the only other major party candidate, came second with 2778 votes.
"We [New Zealand First] knew it was a National stronghold but we weren't going to walk away.
"We just think it is important for democracy that voters have some choice, so we were committed to making sure that Port Waikato had a choice.
Costello said the campaign had been a great experience.
"The extra campaign, a lot more connections, a lot more people to talk to, a lot more door-knocking.
"It is my hometown and I really wanted to make sure that I got to connect with as many people as possible."
Bayly and Costello will work together as ministers in the coalition government.
Costello said "[Andrew]'s run a great campaign. We'll be working together in the future. It's going to be a good relationship."
Bayly said both he and Costello "can work together and make sure that Port Waikato gets the recognition and investment that it deserves."
Bayly's win means Nancy Lu enters Parliament as the 123rd MP - the most the New Zealand Parliament has ever had.
"I feel extremely, extremely grateful for all of the team members and volunteers who have helped throughout the last campaign, for the last six months, and then additionally for another five weeks in this by-election... I'm super grateful to all of their commitment and their time," she said.
"Secondly, to all the voters who have turned out to vote, because it is a huge ask for them to come out [after] just another five weeks and to vote again... I'm very, very grateful and thankful."
Lu's selection means it is the first time National has had two Chinese MPs serve the same term, as she joins Carlos Cheung who won Mt Roskill.
By-election sets precendent
Since 1996, when the MMP system began in New Zealand, there has never been a by-election so soon after a general election. In this case, six weeks.
It was sparked by the death of ACT Party candidate Neil Christensen a week before the general election.
Labour, ACT and the Greens did not stand candidates, with Labour Party president Jill Day calling it 'unwinnable'.
Other candidates stood from Democracy New Zealand, New Zeal, the Women's Rights Party, NZ Loyal, Vision New Zealand, Animal Justice Party and independent Gordon Dickson.
The Port Waikato electorate was established ahead of the first MMP election. It was abolished in 2008 and reinstated for the 2020 election.
The electorate's largest town centre is Pukekohe and includes Pōkeno, Te Kauwhata, Tuakau and Waiuku.
The official results, including special and overseas votes, will be released on 6 December.
- Additional reporting by Liu Chen