Prime Minister John Key said he believed his campaign was still on track, despite the "bomb" that has been thrown since the release of Dirty Politics.
Mr Key told TVNZ's Breakfast programme that he was still receiving good feedback from voters he had been meeting on the campaign trail.
"The left has sat there and said, well we're not going to win if we talk about the economy, law and order, health and education, so let's illegally hack in to a computer and throw some sort of bomb," he said.
He said that the inquiry into Judith Collins' role in an alleged attempt to discredit the former Serious Fraud Office chief executive Adam Feeley would take a long time.
Mr Key told Newstalk ZB this morning that he had received some preliminary advice last night.
"I got some preliminary advice last night that raises a few points that I need to dwell over and get a little more advice on," he said.
The points raised were around the structure of the inquiry, he said.
"Everybody accepts that essentially there's a version of events that Mr Slater might be willing to put on things that aren't necessarily right and I accept the same thing for Judith."
He said Ms Collins stood down as a minister because he believed the inquiry would take longer than the three weeks until election day.
He said that he was "100 per cent crystal clear and rock solid" that he was not involved in the release of Official Information Act documents related to the Secret Intelligence Service to Cameron Slater.