While Australia's election debate continues to whirl around the economy, there is a sleeper in the campaign: one-in-10 voters place the environment and climate change among their biggest concerns.
So far, the green debate has been reduced to the carbon tax and rival schemes, revolving around which form of market economics would best help reduce emissions and foster alternative sources of energy.
Both major parties aim to reduce greenhouse emissions by 5 per cent below 2000 levels by 2020. The Greens want a 40 per cent cut, using 1990 levels as a base. How to get there is the big question.
Prime Minister Kevin Rudd intends switching a year earlier than planned from the present, deeply unpopular, carbon tax to an emissions trading scheme, in theory lowering the price of carbon by as much as 75 per cent.
Opposition Leader Tony Abbott claims the early conversion would strip another A$15 billion ($17.1 billion) from government revenues and would not, in any case, work.
He promises to axe the entire scheme if he wins power.
The debate has flattened to a sloganeering brawl over emissions trading and dumping the carbon tax.
For the rest, the environment has all but vanished beneath big-hitting issues, such as the economy, asylum seekers, the cost of living, health and education.
There is no doubt hard times are pushing the environment down the list of voter priorities. An Australian National University poll found the number citing the environment and global warming as an issue had halved in the past three years, overtaken by the economy, job security, immigration and asylum seekers.
But polls by Nielsen and Morgan reported that the environment was still rated as the most important issue influencing their decision by about 10 per cent of voters. If reflected in the election, this could be significant through support for the Greens and their preferences.
Morgan found that the importance of the environment to voters was as high as 30 per cent in some electorates. The strongest support rests in the capitals, although not in the marginals the major parties are targeting.
But the environment is tricky political ground. The federal Government's power is limited, and intervention can backfire easily in areas where green policies conflict with employment and local economies.
In Tasmania, the Government tried for middle ground in the Tarkine wilderness, where its approval for iron ore mines was overturned in the Federal Court on a technicality. Despite spirited green resistance, it reworked its approval with a list of tight conditions.
Environmentalists were opposed by locals struggling to survive in the state's most depressed region, and blocking the two mines now approved would have hurt Labor at the ballot box.
Renewable energy is another fraught issue. The nation aims to have 20 per cent of its energy from renewable sources by 2020, but there are rows over wind and solar power.
A national movement is raging against wind power, claiming environmental impacts and serious health issues, all rejected by supporters. And solar energy has become so pervasive that it is hammering the sales and profits of power companies.
At sea, the Government's marine reserve is under attack from the Opposition, professional and recreational fishers, and coastal communities.
The Great Barrier Reef is pitting miners and farmers against moves to protect it - rough country for politicians to cross.