By Rob Taylor
CANBERRA (Reuters) - Australia's Prime Minister Julia Gillard hit out at critics of her record on Monday as speculation intensified of a fresh challenge to her leadership and opinion polls showed her divided Labor Party headed for a catastrophic September election defeat.
With Labor on track for a record low vote following months of tensions between Gillard and her main rival, Kevin Rudd, senior backers of the prime minister called for an end to the impasse.
"We certainly can't have this go on. It's just got to be resolved," said Climate Change Minister Greg Combet, one of Gillard's most senior ministers, calling for opponents to come clean and mount a party leadership ballot this week.
"We can't have this kind of speculation continuing on through the election."
A Newspoll in the Australian newspaper was the latest to show conservative opponents leading the government, with 57 percent support compared to 43 percent for Labor.
Opposition leader Tony Abbott has also overtaken Gillard as preferred leader with promises to curb government spending if he wins power, as well as scrap a controversial carbon emissions tax and 30 percent profits tax on coal and iron ore mines.
Abbott also pledged to introduce tougher border security laws to block thousands of asylum seekers arriving from Sri Lanka and transit points in Indonesia, straining ties with Jakarta but winning over many Australians.
Gillard, addressing an economic conference ahead of the last week of parliament before the September 14 election, said critics of her government had made "glaring mis-statements" about Australia's economic health, worrying voters and raising the possibility of the first recession for more than two decades.
"The most irresponsible pessimists have tossed around the 'r' word," Gillard said. "The effect on confidence can only be negative and, on all the facts, is clearly not justified."
She said she wanted her government to be judged on its record of having steered growth of around 2.5 percent in the face of a global downturn, and delivering relatively low unemployment of 5.5 percent.
Gillard said the leadership issue was "settled" in March, when she won a surprise vote against Rudd unopposed, the third such ballot she has carried.
"What I want to leave this week having achieved is better schools for our nation, which means a better future for our nation," she told reporters.
Any return of Rudd as prime minister could force Australia's governor-general, the titular head of state, to intervene. Options could include calling an immediate election as Rudd does not have agreed support from independent lawmakers who wield the balance of power in parliament.
Gillard, 51, has struggled to win support from Australian voters since she toppled Rudd to become prime minister in a Labor party coup in June 2010.
She led the party to dead-heat elections in August 2010, and held onto power by one seat after striking deals to ensure the support of independents and the Greens.
Rudd, 55, led Labor to an election victory after almost 12 years of conservative rule, but he was dumped in favor of Gillard in June 2010 after his government become embroiled in a damaging fight with the mining industry over a planned new tax.
(Editing by Ron Popeski)