The announcement of plans by Labour and the Greens for the electricity industry has had a profound impact on investors' intentions towards the Mighty River Power share sale.
If they form the next government, Labour and the Greens intend setting up a single purchaser of electricity.
A Shareholders Association survey of 400 active retail investors shows investment interest has fallen. Before the announcement, 72% wanted to buy Mighty River Power shares; 36% of those questioned in the survey want to buy.
Just under 54% said they will be investing less money in Mighty River than they originally intended.
Association chair John Hawkins says the results illustrate the impact the policy announcement has had on investors' decision-making.
A senior associate at the Institute of Government and Policy Studies, Geoff Bertram, says it's no surprise investors are backing off, given what he calls the radical uncertainty they face.
He says he hopes first-time buyers will be given an explanation of how the different possible regulatory regimes would affect share prices.