The public is highly polarised about whether the "tea cup tape" should be released, a poll suggests.
Prime Minister John Key and Act Party candidate John Banks have both refused to give authorisation to release the tape, containing a conversation between the two which they thought was private.
A nationwideHorizonPoll found that 53 per cent of people do not believe the politicians should authorise the public release of the recording, while 46.9 per cent think they should.
The poll also shows that 54.9 per cent of people believe the recording was a deliberate ploy by the media, while 15.9 per cent believe it was inadvertent, 29.2 per cent are not sure.
Asked if the Herald on Sunday, which has the recording but decided not to publish, or other news media should publish it now, 49.4 per cent said no, 39.5 per cent yes and 11 per cent said they are not sure.
The poll suggests the affair has been damaging to the Prime Minister's reputation, with 41.9 per cent saying it has made him less credible, 6.2 per cent more credible and 47.4 per cent saying it makes no difference.
Among National Party supporters, 17.7 per cent think the issue has made the Prime Minister less credible and 12.3 per cent more credible - a net credibility loss of 5.4 per cent.
Thirty-nine per cent think it has made Mr Banks less credible, 3.2 per cent more credible.
The poll also asked whether the issue has impacted New Zealanders' view on the credibility of the Herald on Sunday, with 43.1 per cent thinking it made the newspaper less credible and 11.8 per cent more credible.
It has also been damaging to the news media in general, with 38.6 per cent believing has it made it is less credible, 9.8 per cent more credible.
* The poll questioned 2,874 adult New Zealanders and has a margin of error of +/- 1.8 per cent.
