The battle for the Auckland mayoralty this year is likely to be another big-spending affair, following the failure of a move to reduce the cap on campaign spending.
By a two-vote margin, Parliament has rejected Labour MP Phil Twyford's bid to limit individual candidates' spending in the official three-month campaign period.
Mr Twyford wanted a cap of $376,000 in the campaign period to ensure that there was no advantage to wealthy candidates.
The law currently uses a population-based formula so the $580,000 limit that applied at Auckland's last mayoralty election will almost certainly be raised for the poll in October.
Three years ago, both the successful Len Brown and the defeated John Banks spent more than $500,000.
A $70,000 limit applies in the other largest cities.