Aucklanders eyeing the Super City mayoral contest are deserting Manukau Mayor Len Brown following his council credit card breaches, a survey shows.

An online survey of readers of the Herald and other APN publications shows 13.6 per cent of respondents have switched allegiance from Mr Brown to Auckland City Mayor John Banks, or another candidate.

Even though the survey is unscientific, the large number respondents - 1537 readers of the Herald, Herald on Sunday, the Aucklander and Woman's Weekly - provides an interesting take on the two weeks of intense political and media scrutiny of Mr Brown's credit card expenses.

When readers were asked who they would vote for as Super City mayor, Mr Brown got 31.2 per cent support, narrowly ahead of Mr Banks on 29.1 per cent. A further 12.9 per cent said they would vote for another candidate and 26.8 per cent did not know.

Last month, a scientific Herald-DigiPoll survey showed Mr Brown with 48.4 per cent support to Mr Banks' 37 per cent in a head-to-head match-up.

The past fortnight has tested Mr Brown's political career after it was revealed he used his council credit for personal purchases totalling $638.27 and broke the council's credit card policy despite warnings from senior staff. He has repaid the council for personal spending and in an emotional address on Tuesday apologised to councillors.

Mr Brown declined to comment about the survey, but his mayoral spokesman David Lewis called it an interesting snapshot that showed support for the mayor holding up.

"Now is the time to get back and focus on the issues that are important to Auckland," Mr Lewis said.

In an online "Letter to Manukau" yesterday, Mr Brown said he had been subjected to personal attacks from a number of fronts and there had been much comment about the emotional nature of Tuesday's speech to councillors where he beat his chest and head as part of a Maori gesture.

He said he was emotional because he was looking at the faces of former leaders hanging on the council chamber wall. He saw council chief executive Leigh Auton, who had been with the council for 30 years, and thought about the 45 years of history of Manukau and the politicians and officers who had built a great city with tremendous pride.

He acknowledged his wife, Shan Inglis, "who has stood by me like a rock", adding: "Without her by my side I would not be mayor of this city.

"I therefore want to assure our communities that the vast majority of our council are totally united in the expectations that our council should conclude its time with dignity and that we will ensure that the affairs of our council are managed appropriately to its conclusion," said the first-term mayor.

Mr Banks declined to comment on the survey but said: "It is only 3 months before the people of Greater Auckland will make arguably the biggest decisions of their lives around the future of this city.

"We are going to be out on public platforms debating the important issues. It is up to voters to decide who is best qualified."

* "I don't think he was trying to fiddle the system. He was just a bit careless with his paperwork."

* "This business with the credit cards is just scaremongering through the media."

* "There are more important issues facing Auckland than what he bought with the council credit card."

* "This is a beat up by the Mayor's opponents. Len Brown is honest, sincere, personable, well loved and he cares. Genuinely."

* "If we can't trust him with a credit card, how could we trust him to run a Super City?"

* "He showed a lack of judgment and on television he was too emotional. A Mayor needs to be a clear thinker and set an example."

* "He's clearly got his snout in the trough and despite his short term as Mayor has developed an expectation of entitlement."

* "The public has now observed Len Brown under pressure and he does not stack up."

Source: Feedback from Herald reader panel