Australia's potential next prime minister too moderate for some in conservative party

While some in Australia's ruling Liberal Party consider Prime Minister Tony Abbott too conservative, the main criticism of his rival Malcolm Turnbull — potentially the nation's next leader — is that he's too moderate.

The 60-year-old former lawyer and merchant banker is the type of classical liberal that has become rare in the oddly named party, which has been overrun by conservatives in recent decades.

Turnbull is widely regarded as the most likely candidate to replace Abbott as prime minister, if not at an internal government leadership debate Monday then possibly in another challenge before elections next year if Abbott cannot improve his administration's popularity.

Turnbull was opposition leader for two years before he lost a party-room ballot by a single vote to Abbott in 2009. His downfall was his belief that Australia should make polluters pay for their greenhouse gas emissions.

His stance seems to have wavered more recently, with Turnbull saying on television last year that "emissions trading schemes seemed to work better in theory than in practice."

Abbott's government ditched Australia's carbon tax last year and has introduced a 2.55 billion Australian dollar ($2 billion) fund of taxpayers' money to pay the worst polluters incentives to operate more cleanly.

Unlike Abbott, Turnbull also believes that Australia should lift its ban on gay marriage. It's not a surprising position for a politician whose electoral district hosts the annual Sydney Gay and Lesbian Mardi Gras.

Opinion polls show that Turnbull, the government's communications minister, is a more popular politician than Abbott. But Turnbull's critics point out that polls also show that Australians who like him tend to vote for the center-left Labor Party opposition. He is less popular among conservatives.

Abbott and Turnbull were both Rhodes scholars, but they differ on whether the British monarch should remain Australia's head of state.

Turnbull was chairman of the Australian Republican Movement — a group unrelated to the American political party — which argued the case for Australia severing its constitutional ties with Britain and appointing an Australian citizen as president. The status quo was maintained in a referendum in 1999, largely because Australians were divided over whether the president should be appointed by the government or elected.

Nicknamed "The Silvertail," an Australian term for the wealthy and influential, Turnbull was the richest member of Parliament until mining magnate Clive Palmer was elected in 2013.

While he was not born into privilege, Turnbull's critics accuse him of having an arrogance that ordinary Australians don't relate to.

His father was a Sydney hotel broker who became a single father when his wife, a radio actress and academic, abandoned the family when Turnbull was 9 years old.

He became a household name in Australia as a lawyer in the 1980s when he succeeded in blocking a British government attempt to prevent Australian publication of "Spycatcher," a memoir by former British intelligence officer Peter Wright.