In starting the five-week election campaign, Rudd said the economy can no longer rely on Chinese demand for iron ore and coal that made the country one of the few wealthy nations to avoid a recession during the global economic downturn. "The boom, of course, has fuelled so much of our nation's wealth,'' he told reporters at Parliament House. "That boom is over,'' he said.

"Who do the Australian people trust to best lead them through the new economic challenges that lie ahead?'' he asked.

Rudd conceded that his center-left Labor Party was the underdog, saying his advisers had told him that if the election had been held this weekend, his government would have lost.

But opinion polls also show that more voters prefer Rudd, a 55-year-old Chinese-speaking former Beijing diplomat, as prime minister than opposition leader Tony Abbott, a former Roman Catholic seminarian and journalist who is also 55.

The election promises to be an extraordinary contest for Australian politics. Labor leads Australia's first minority government since World War II, and polls suggest the opposition faces an easier task picking up seats than Labor does.

Labor holds 71 seats in the 150-seat House of Representatives where parties form governments. The opposition holds 72 seats, with the remainder held by independent lawmakers or sole legislators from minor parties.

Rudd said the September date meant he would not attend the G20 meeting in Russia that week, but Australia would likely be represented by Foreign Minister Bob Carr.

Poll shows 26 % support for Assange

CANBERRA: WikiLeaks founder and Australian Senate candidate Julian Assange says he is proud of the level of support he enjoys in his home country ahead of federal elections on September 7.

A national survey by Sydney-based UMR Research, a company which Labor relies on for its own internal polling, found in April that 26 percent of Australian voters said they were likely to vote for Assange or other candidates running for his WikiLeaks Party in national election. "I'm obviously proud of that,'' Assange said.

UMR managing director John Utting told Fairfax Media in April said that the poll showed WikiLeaks had "a good chance'' of winning seats if Assange runs a clever campaign. A senate seat can be won with as little as 17 percent of the vote within a state.