Support for Julia Gillard and her government has slumped, wiping out most of the gains made since the carbon tax was introduced last year and raising the chances that she could be replaced by Kevin Rudd.
Tony Abbott now leads Ms Gillard as preferred prime minister for the first time in seven months, although Mr Rudd declared on Sunday that he would not be drafted into the Labor leadership.
Gillard trending down: Pollster
Worrying numbers for the Gillard government in the first Fairfax/Nielsen poll of 2013. John Stirton discusses the results.
His comments, however, preceded the release of the latest Age/Nielsen poll, which found the gap between Ms Gillard and the former prime minister has grown, with Mr Rudd favoured by 61 per cent of voters compared with 35 per cent for her.
The ALP is gripped by internal tensions over the possibility of a leadership change, but Mr Rudd, who fuelled speculation last week with criticism of the mining tax, used his sixth high-profile TV appearance in a week to dismiss the talk.
''A couple of weeks ago I said everyone should take a cold shower,'' he said on Sky News' Agenda program. ''Last Friday I said they should have an ice bath. It's time this debate was put into cryogenic storage.''
Labor's support, which had climbed to the mid-30s, has collapsed - plunging it back towards landslide-loss levels were an election held now.
Its primary vote stands at 30 per cent, a dip of 5 points since December and only 4 points above its nadir of 26 per cent last May.
Support for the Coalition rose by 4 points, taking its primary vote to 47 per cent - its highest level since just after the carbon tax took effect last July.
Support for the Greens was steady on 11 per cent.
On a two-party-preferred basis, Labor's support was on 45 per cent to the Coalition's 55, according to voter feedback on where they would direct their second-preference votes. Based on preference flows from the 2010 election, the two-party split is 44/56 in favour of the Coalition.
Prime Minister Julia Gillard said on Monday that she just lets poll results ''wash through''.
''If I spent my time worrying about and commentating on opinion polls, then I wouldn't have time to get my job done,'' she said.
Poor poll trend continues for Labor
The latest Fairfax/Nielsen poll points towards a landslide election loss for the government. Mark Kenny in the Breaking Politics studio.
But pollster John Stirton said the results were a bad sign for the government in an election year.
''It confirms that the trend to Labor that ran from May to November last year, and appeared to stall over Christmas, is now heading in the opposite direction,'' he said.
As well, Mr Abbott has overtaken Ms Gillard as preferred prime minister, with his support leaping 9 points to 49 per cent. Support for Ms Gillard was on 45 per cent - down 5 points.
Labor strategists have previously pointed to her superior popularity as an important reason to retain her as leader.
The poll results follow a poor fortnight for Labor in which Mr Rudd returned prominently to the airwaves and Treasurer Wayne Swan admitted that his mining tax had raised almost no revenue.
Less than one-quarter of voters now support the mining tax in its current form, with two-thirds in favour of either dumping it or making it stronger.
The national poll of 1400 voters was taken from last Thursday to Saturday.
The snapshot of voter sentiment coincides with a Galaxy poll published by News Limited newspapers on Sunday that showed female voters, thought to be a bulwark for Ms Gillard in holding off Mr Abbott, were walking away, with 36 per cent supporting the Prime Minister.
Mr Stirton said it was possible that women had led the move away from Ms Gillard.
''There is some evidence that the fall in Labor's vote was greater among women than men, but we will need another round of polls to confirm this,'' he said. ''On the other hand, the surge on Abbott approval came more from men than women, but again the difference was probably not statistically significant.''
Malcolm Turnbull also continues to lead Mr Abbott as preferred Liberal leader, but his lead has narrowed.
While net approval for both the Prime Minister and Opposition Leader remains in the negative, with voters clearly unimpressed by both, Mr Abbott's net approval rating improved by 16 points, with an 8 per cent gain in voters who approve of his performance and an 8 per cent drop in those who disapprove.
Ms Gillard's numbers, however, went the other way, with disapproval climbing by 6 points. Her approval stands at 40 per cent and disapproval at 56 per cent - a net rating of minus 16.
Mr Abbott's approval stands at 42 per cent and disapproval at 55 per cent - a net rating of minus 13.
The result reflects Labor's untidy start to the election year in which Ms Gillard promised solid and steady government and progress on key social reforms such as the National Disability Insurance Scheme and the Gonski reform of school education funding.
Ms Gillard broke with tradition earlier this month to fix the election day for September 14, nearly eight months in advance.
She cited the need to remove election timing uncertainty and make way for orderly governing rather than campaigning. How-ever, unforced errors, backtracking on the budget surplus and embarrassment over the mining tax performance have undermined the government's pitch.