- A political scandal has engulfed New Zealand politics ahead of elections this month
- It was sparked when a journalist published the hacked emails of a blogger
- He says the emails show a strategy by the government to smear political opponents
- A senior minister has resigned, yet the government still leads in polls
New Zealand politics, concedes Bryce Edwards, one of the country's leading commentators on the subject, "can tend to be on the bland side compared with other countries."
And at the start of last month, New Zealand's impending September 20 general election looked set to be just that: a tame affair, with an all but foregone conclusion.
The center-right National government, led by perennially popular Prime Minister John Key, enjoyed a huge lead in the polls and seemed destined to amble its way to a third term in power.
But then a bombshell struck in the form of a book-length piece of investigative journalism, triggering a cascade of scandals that have thrown the political parties' campaigns into disarray and dominated the news cycle for weeks.
"No campaign in living memory compares to the 2014 campaign," said Edwards, a lecturer in politics at the University of Otago.
"New Zealand election campaigns are usually fought over a mixture of policy and personalities," he told CNN, "not over issues of integrity and corruption and wrongdoing."
Last month, long-time freelance investigative journalist Nicky Hager published "Dirty Politics." The book is based on a cache of emails and social media messages hacked from the private accounts of the controversial right-wing blogger Cameron Slater, whose "Whale Oil" blog is widely read.
Slater, a polarizing and politically well-connected figure whose father is a former National Party president, is notorious for his abrasive style and for breaking a string of scandals, including an extramarital affair by the mayor of Auckland last year. The mayor subsequently acknowledged the affair.
Hager's book alleges close and sustained cooperation between the blogger and senior government figures -- including a senior minister and top prime ministerial aides -- in their concerted efforts to smear political adversaries.
The extent of the alleged collaboration suggested in the hacked emails surprised even the book's author, he told CNN.
"This was prime ministerial staff involved in coordinating and executing attacks on the government's political opponents," said Hager. "It was much more orchestrated and constant -- relentless -- than anyone had been aware."
In the book's wake, a senior National lawmaker, Judith Collins -- who admits to a close friendship with Slater -- has resigned as justice minister over leaked emails suggesting she was involved in a campaign to undermine the head of the government's Serious Fraud Office.
Collins would not comment to CNN, but has previously told reporters she is innocent of the allegations against her, and is confident she will be exonerated by an independent government inquiry into the issue, one of two official investigations launched to probe matters raised by the leaks.
The other investigation will be conducted by the Inspector-General of Intelligence and Security -- the watchdog for the Security Intelligence Service (SIS), a national intelligence agency -- into allegations that secret information had been declassified and passed to Slater for political purposes.
The scandal has put the prime minister's relationship with the blogger under close scrutiny. Key has told reporters that he talks to Slater three or four times a year, and occasionally sends the blogger a text message when he doesn't understand a story he has written.
Key would not comment to CNN on his relationship with Slater or the allegations made by Hager, other t