With 4000 copies sold by lunchtime and several thousand already on back order, Nicky Hager's bombshell has "overwhelmed" the book industry.
Hager's book, Dirty Politics: How attack politics is poisoning New Zealand's political environment, launched last night, is based on thousands of emails revealing the extent of the relationship between Slater and prominent National Party figures.
The executive director and publisher at Craig Potton Publishing, Robbie Burton, said the entire first run of Dirty Politics - 4000 copies - sold out by lunchtime today.
"Truth is we've been completely overwhelmed by the level of interest," he said.
Several thousand were on order for tomorrow morning, and the printers were "going for it" until demand slowed.
Burton said it was difficult to predict the book's popularity, but he did not expect it to sell so fast and he would have been happy with 4000 copies sold.
"I'm thrilled that people still want to read books about a subject like this," he said.
"It's nice for us in the industry to know there's still a place for this kind of long-form analysis. It's gratifying."
He said an ebook would be on offer through Wheelers today.
Unity Books Auckland owner Jo McColl said she had been selling books for about 35 years but never experienced demand like this.
Before the store opened today, all its copies of Dirty Politics had been sold via orders.
"One of our staff was on Twitter until 11pm taking orders from home," she said.
Public interest had been "completely out of the blue".
"No [shop] was given a chance to order; it was just a blind number," she said.
"We were sent a pathetically small number. To be fair, I still would have vastly underestimated it.
"Nicky's books have always gone well, but they usually take a little while to chug into gear.
"But this has just come roaring out of the gates like I've never seen before."
The media, political parties and men and women of all ages had placed orders, she said.
With another 300 copies arriving tomorrow morning, and 150 already on back order, Unity was set to sell out again.
"It was about this time last year The Luminaries came out and we were just wondering how we were going to beat those figures," she said.
Nielsen Book Services listed The Luminaries, by Eleanor Catton, as the top-selling title in New Zealand last year with more than 42,000 copies sold.
— Robbie Ellis (@ellisrobbie) August 14, 2014
— Simon Bradwell (@simonbradwellnz) August 13, 2014
Jono Galuszka: “#dirtypolitics sold out at both Whitcoulls stores in Palmerston North before 10am this morning”
#dirtypolitics sold out at both Whitcoulls stores in Palmerston North before 10am this morning.
— Jono Galuszka (@jonogaluszka) August 13, 2014
— Greville Whittle (@GrevilleWhittle) August 13, 2014