A poll of people who've already voted in the Auckland super city election puts Len Brown ahead of John Banks by a considerable margin.
The survey by Horizon Research, published in the Sunday Star Times, is based on a sample group of just 570 people.
Centre-left Manukau mayor Len Brown has the support of 49% of those questioned, while Auckland mayor John Banks was on 23% support.
The poll's margin of error is +/- 4.1%.