Celia Wade-Brown has ousted Kerry Prendergast as Wellington mayor in the closest election race the capital has seen.

Ms Wade-Brown, of the Green Party, took the mayoralty after the counting of special votes was completed this afternoon.

She beat three-term mayor Ms Prendergast by a total of 176 votes (24,881 to 24,705), believed to be the closest mayoral race the capital has seen, after being behind by 40 votes on election day, council spokesman Richard Maclean said.

A total of 632 special votes were included in the result, Mr Maclean said.

In a statement released after the result, Ms Prendergast congratulated Ms Wade-Brown and said it had been an honour to serve as mayor for nine years.

"It goes without saying that I am tremendously disappointed at the outcome of the election. But I congratulate Celia and sincerely wish her all the very best for the huge job she now faces," she said.

"It has been the best job in the world, and I will miss it."

She had no immediate plans for the future but would be able to spend more time with family.

"After working 12-hour days for nine years, it will be a huge change for me and it will take me some time to get used to it."

She expressed her thanks to friends, family, supporters and councillors and staff she worked with while mayor.

Ms Wade-Brown campaigned for better public transport and light rail.

Green MP Sue Kedgley told the Dominion Post that the Green Party has a history of doing well in special votes.

The Green party crossed the 5 per cent threshold to enter parliament in 1999 only after special votes were counted, she said.

Ms Prendergast said before today's result was known that the Single Transferable Vote (STV) system could cost her the election.

She said Ms Wade-Brown could not beat her but STV could.

Ms Prendergast served as mayor of Wellington from 2001 and was the city's second woman mayor.

Celia Wade-Brown - who is she?

Love her or loathe her, Wellingtonians could hardly say they did not know their three-term mayor, Kerry Prendergast. But with special votes today casting her from office, many in the capital city may be wondering who is Celia Wade-Brown?

Ms Prendergast had been expected to romp home once again, but when counting concluded on Saturday she was only up by 40 votes and the Green Party candidate and current Wellington City councillor Ms Wade-Brown was always a chance to sneak in through special votes.

Ms Wade-Brown is certainly no stranger to Wellington politics. The 54-year-old was first elected to Wellington City Council in 1994 and has been there ever since, apart from a gap between 1998 and 2001. She is currently the Environment Portfolio leader, and chairperson of the Waste Forum - Wellington Region.

According to her campaign website, Wade-Brown was born in Paddington, London, and following a gap year spent in Ghana after school she moved to Wellington in 1983, buying a home in Island Bay.

She says she "fell in love with this compact city, its wild spaces and the wooden houses perched on the hills".

"In fact, I loved it so much that I bought one of those wooden houses, overlooking Cook Strait, where I still live with the New Zealander from Invercargill I married, our two sons and a black Labrador named Storm."

Those sentiments are what shape her policy priorities, outlined on the elections2010 website.

At the top of the list for the "beautiful compact city" is "good transport choices", with Ms Wade-Brown preferring "cleaner buses, light rail and active transport" over "costly flyovers and tunnels bringing more cars into the city, looking for parking".

The next policy priority listed is "good technologies", including renewable energy drawing on the "awesome forces of the Cook Strait" and local biofuels.

Ms Wade-Brown's green theme continues, stating "community wisdom can help answer many complex social and environmental issues", and looks to community gardens and the sharing of mending, cooking and carpentry skills to reduce the cost of living for families.

Ms Wade-Brown promises "trust and inclusion", does not support a city-wide liquor ban, opposed the construction of a Hilton Hotel on the "T" of Queen's Wharf, and states she fought for heritage protection on the waterfront, in the central city and in residential areas.

"My vision for Wellington includes light rail for less traffic congestion, and safer walking and cycling. Creative enterprise, fair trade, fast broadband, and clean new technologies provide good jobs.

"Our compact and beautiful capital is where we choose to live, work and play. Green hills and healthy oceans surround our cosmopolitan heart."

So there it is - the windy city has gone all green.