The Green Party has collected more than 100,000 signatures for a petition to force a referendum on asset sales, with almost 200,000 signatures now gathered in total.
The Greens are part of the Keep Our Assets Coalition that includes community groups, non-government organisations, unions and the Labour Party, and is pushing for a citizens' initiated referendum on the Government's asset sale policy.
The coalition as a whole has collected nearly 200,000 signatures and said it was collecting signatures at the rate of about 2000 a day.
The coalition's petition was launched in April this year, and it has until May next year to collect 310,000 valid signatures to trigger a referendum.
Green Party co-leader Russel Norman said a referendum was likely, gauging by the speed signatures were being collected.
Dr Norman said the Greens had collected more than 1000 signatures a day on average over the past three months.
"Our MPs have also been out on the streets helping to collect signatures and are getting great feedback from the public.''
"A Citizens' Initiated Referendum on asset sales will give New Zealanders the chance to send the Key Government a clear message that they don't want our assets sold.''
"The Government's asset sales programme and the costs involved have changed substantially from that pitched by John Key in the 2011 election.
"John Key should put his more costly asset sales programme up before the public and see what the result is.''
Some of the signatures were collected with the help of eight fulltime staff members at the cost of $75,000 to taxpayers.
The party used the Leader's Office fund to hire the equivalent of eight fulltime staff members in an attempt to force a citizens' initiated referendum before the Government begins to sell state-owned power companies.
The payments were permitted under parliamentary rules, but it is the first time the funds were used to gather support fort a party policy.
The National Party attacked the Greens in June over their use of taxpayer money to collect signatures for a referendum on asset sales - but would not rule out doing the same for its campaigns.
Dr Norman said the Greens had been transparent about spending.
He asked a question in the house about how much the National Party had budgeted to advertise and promote its asset sales programme, and said it was about $1.1 million.