LABOR is hoping the vanishing ''Brown factor'' will allow it to claw back three or four points on its weak primary vote in southern states.
While Labor's woes in Queensland, Western Australia and NSW have dragged down the Gillard government, Bob Brown's decision to depart politics in June has raised hopes of paring back what is seen as an inflated green vote south of the Murray River.
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Christine Milne takes a swipe at big business as she settles into her new role as Greens leader.
But yesterday the newly elected Greens leader, Christine Milne, sought to shore up her party's support after Senator Brown's surprise resignation on Friday with a promise to sell an economic vision for Australia.
She rejected Labor's drive to return the budget to surplus and said economic policy had to be flexible. ''The difference is that the Greens want to look at economic tools as a way of facilitating outcomes for the community,'' Senator Milne said.
''We look at what sort of society would Australia want in the future. The boom is going to end. We want an investment in education, research and development and we support the government's priority for schools' training … to make sure that we have money to invest in our children's education.''
But some Labor insiders believe Senator Brown's personal popularity made up a considerable portion of the Greens's vote, given his high profile over decades as an environmental campaigner, anti-war activist and champion of social change.
The Greens won more than 11 per cent of first preferences across Australia at the 2010 election and opinion polls since suggest they have an even higher primary vote in Tasmania, Victoria and South Australia.
In contrast, recent polls show Labor has slipped back almost 9 percentage points in Victoria and almost as much in South Australia on its 2010 result. The drop-off in the government's primary vote in NSW is almost 7 percentage points since the election.
The Liberal frontbencher Christopher Pyne told ABC TV yesterday the Greens had made no progress at state elections since teaming up with Labor federally and that the Greens had actually gone backwards in the past 18 months. But he conceded any decline in the Green vote could help Labor.
Even before Senator Brown's resignation, there was muttering inside Labor about how to deal with the minor party, especially as the carbon tax - the price of Greens support in the hung parliament - had already passed.
Some Labor insiders argue privately there will come a time to pick a fight with the Greens to escape the Coalition's attack on it as in the thrall of its junior partner - though others warn the fight could be started by the Greens, so as not to be seen as too close to the government of the day.
Senator Milne told Ten's Meet the Press she had spoken to the Prime Minister, Julia Gillard, yesterday and given an assurance the signed agreement between the Greens and Labor still stood.
Senator Brown had walked away from one aspect of the deal in January, cancelling regular meetings with Ms Gillard over a dispute with Tasmanian forests. He agreed in recent weeks to resume weekly meetings when Parliament is sitting.
Senator Milne said Labor had boxed itself in to delivering a budget surplus and blamed the Opposition Leader, Tony Abbott, for painting Ms Gillard as a liar.
''It's all about the Prime Minister and the government having decided that they can't be seen to change their mind,'' she said.
''That's the tragedy of the actual political debate around the economy at the moment - we need to be creating the space for people to change their minds and be able to nuance a position, according to what's going on in the world.''
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