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Australian Prime Minister Tony Abbott has conceded that he could be ousted after only 16 months in power when his ruling party meets Monday to discuss whether the country needs a new leader in the face of dismal opinion polling and a voter revolt against conservative state governments.

The challenge to Abbott's leadership — a "spill motion" that declares the party leadership open to any candidates in a ballot — was triggered by disgruntled government lawmakers last week and was to be discussed Tuesday at the year's first scheduled meeting of the ruling Liberal Party's 102 lawmakers.

But Abbott on Sunday arranged a special meeting for Monday morning, leaving some lawmakers scrambling to book earlier flights to the nation's capital, and giving his opponents less time to garner support to overthrow him.

Asked whether the meeting could dump him, Abbott told Australian Broadcasting Corp. television late Sunday: "It could. Obviously."

"It's a pretty chastening experience to have a spill motion moved on you after just 16 months in government — a very chastening experience — and I am determined that my government, if it continues after tomorrow, will learn from this experience, will be different and better this year than we were in every respect last year," Abbott said.

If the motion passes Monday, the positions of prime minister and his deputy, Foreign Minister Julie Bishop, will be declared open. There would then be secret ballots of Liberal Party lawmakers to either return Abbott and Bishop or replace them.

Abbott is counting on a majority of his party colleagues defeating the motion so that the ballot does not take place and the level of his support is not tested. Around two-thirds of lawmakers appeared Sunday likely to reject the motion, although the situation remained fluid.

No lawmaker has yet announced whether he or she would be prepared to run against Abbott if the motion passed.

Communications Minister Malcolm Turnbull, who led the party in opposition until he lost to the more conservative Abbott in a leadership ballot in 2009 by a single vote, is touted as the favorite to replace the prime minister. Turnbull refused to say Sunday whether he would contest the leadership.

Abbott has come under increasing criticism from some members of his own party — which is conservative despite its name — over the government's sagging approval ratings. Polls have slumped since May, when the government's first annual budget was widely criticized as being toughest on the poor and most vulnerable.

A polarizing figure, Abbott likes to project himself as a macho man of action, but he also has image problems, particularly among female voters.

Recently, he drew widespread criticism by making Queen Elizabeth II's 93-year-old husband, Prince Philip, an Australian knight on Australia's national day. Many saw it as an insult to worthy Australians.

Public dislike of Abbott has been blamed in part for big election losses for conservative governments in Victoria state in November and Queensland state last month.

Government lawmakers had mixed reactions to the news that the leadership crisis would be discussed hours before Parliament is due to sit for the first time this year. Some first heard of the change through the media.

Arthur Sinodinos, a senator who is critical of Abbott and who has announced his support for the motion, said his colleagues' decision should not be rushed. Party members "should be given time to discuss the matter at hand. Tuesday is the time to do that. It is disappointing," Sinodinos told Fairfax Media.

Government lawmaker Teresa Gambaro issued a statement Sunday accusing Abbott of "belligerence and hubris," and of creating "an internal climate of fear and intimidation" in the party since he became its leader more than five years ago.

Lawmakers could be influenced by an opinion poll published Sunday by News Corp. newspapers that found the government would be more popular with Turnbull at the helm, but would still trail the opposition center-left Labor Party.

The poll by market researcher Galaxy Research found that the government currently trailed Labor 57 percent to 43 percent. Under Turnbull, 49 percent of respondents would prefer the Liberals and 51 would prefer Labor. Newspapers did not publish the poll's sample size, methodology or margin of error. They did not say when the toll was taken.

Turnbull is a multi-millionaire former merchant banker whose nickname is "The Silvertail," an Australian term for the wealthy and influential. He supports legalizing gay marriage and lost the party leadership over his support for an emissions trading scheme proposed by the then Labor government.

Abbott wants to maintain Australia's ban on same-sex marriage and is opposed to making polluters pay for their greenhouse gas emissions. His government made good an election promise by abandoning Australia's carbon tax last year.