National's Nick Smith is at risk of losing the seat he's held for 24 years.
"If I'm brutally honest, we can't come back from this," Smith reportedly told the crowd in Nelson.
More than 50 per cent of the votes have now been counted for the Nelson electorate, with Labour's Rachel Boyack leading Smith by nearly 4000 votes.
She's trying to keep her excitement in check.
Brigette Morton predicted there was a night of carnage ahead for many National Party politicians.
With 6.4 per cent of the vote counted, National is well behind on 26 per cent.
"This is a tough night for many National supporters and many National MPs," outgoing National MP Nikki Kaye told TVNZ.
Sitting National MP Simon O'Connor also looks like he could have a tough fight to retain the Tamaki electorate, with just a 23-vote lead over Labour candidate Shirin Brown with 4.9 per cent of the vote counted.
National could also be set to lose the Upper Harbour electorate, previously held by the departed Paula Bennett. National's Jake Bezzant currently trails Labour's Vanushi Walters by 420 votes, with 19.1 per cent of votes counted.
National Party president Peter Goodfellow said the party had been running a Covid campaign and it was very hard to get any cut through.
He said 30 per cent was a great base to run a strong opposition. "I think we need to do that and hold the Government - whatever it looks like - to account."
He praised leader Judith Collins, saying members felt she had done a tremendous job running the campaign, particularly through the second Covid lockdown in Auckland.
National Party deputy leader and campaign manager Gerry Brownlee said it was a campaign hampered by Covid.
"You've got take some responsibility I suppose but I think Judith ran an incredible campaign. Overwhelmingly it was the response to the Covid lockdown and the great position that New Zealand ended up in that was at play here," he told Mike Hosking.