It was all celebrations at the Act Party’s function on the Auckland waterfront last night after securing its best result and the icing on the cake being deputy leader Brooke van Velden defeating National’s Simon O’Connor in the blue ribbon seat of Tāmaki.

At 9.45pm, van Velden was more than 3500 votes ahead of O’Connor with 60 per cent of the vote counted.

She was welcomed to the celebrations with rapturous applause by supporters. “I really look forward to serving the local people of Tāmaki,” she said.

Brooke van Velden at last night's celebrations. Photo / Jason Oxenham

For O’Connor, it’s the end of the road after 12 years as the MP for Tāmaki - a seat once held by former prime minister Sir Robert Muldoon.

Party leader David Seymour was also on track to hold the neighbouring seat of Epsom, with a comfortable 5000-plus majority after two-thirds of the vote had been counted.

On the party vote, Act was sitting on 9.25 per cent, which along with 41.07 per cent for National, gives the two centre-right parties 63 seats in the 120-seat Parliament. Act would get 11-12 seats on current voting numbers.

Act, whose name comes from the initials of the Association of Consumers and Taxpayers, was founded in 1993 by Sir Roger Douglas and Derek Quigley and, for the first time, will play a key role in government under the leadership of David Seymour, who has been an MP and leader of the party since 2014.

Act’s third-ranked candidate Nicole McKee said the numbers were looking positive given they were up on 2020.

Asked if it was a big relief that NZ First might not be needed to form a government, McKee exhaled a big breath and nodded.

MP Toni Severin is 14th on the party list and would not return to Parliament on current numbers.

Brooke van Velden and Simon O'Connor contested the Tāmaki seat. Photo / Dean Purcell.

Severin said “there’s still hope”, saying she expected the party might get more support from some rural areas which hadn’t been counted.

Another MP Chris Baillie also wouldn’t return on these numbers.

McKee said it would be really sad to see the pair not come back to Parliament.

Act’s 12th list candidate, Antonia Modkova, said she was “absolutely stoked” at the prospect of becoming an MP.

Cameron Luxton, 11th on the list, said he was pleased to see the party had increased its vote from 2020, saying it was all Act could have hoped for.

On possibly becoming an MP, Luxton said he had told his wife that after tonight he would be working as an MP or a builder.

”It looks like I’m going to be an MP.”