CANBERRA — Prime Minister Kevin Rudd called an election for Sept. 7 and said Sunday that it will be fought over who can be trusted to manage the Australian economy as it transitions from a decade-old mining boom fed by Chinese industrial demand that is now fading. 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. “Who do the Australian people trust to best lead them through the new economic challenges that lie ahead?” Rudd asked at a news conference at Parliament House. 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. Latest economic figures show a sharp decline in the nation's finances, with the Treasury Department last week raising its estimated deficit for the current fiscal year to 30.1 billion Australian dollars ($26.8 billion) due to the mining slowdown. The new forecast for the year ending June 30, 2014, was AU$12 billion worse than the department's last forecast in May. The government also announced a AU$33.3 billion shortfall in the revenue forecast over the next four years — a deterioration of about AU$3 billion a week since the May forecast. Economic growth for the fiscal year, forecast at 2.75 percent in May, was downgraded on Friday to 2.5 percent. The unemployment rate forecast in May to rise to 5.75 percent in the current fiscal year was revised up to 6.25 percent. The conservative Liberal Party-led opposition coalition has accused the government of wasting money on stimulus spending after the last conservative government delivered surplus budgets year after year until it lost power in 2007. But economists largely applauded Labor's early spending. After the election was announced, Abbott promised to “get the budget back under control,” and listed scrapping the unpopular carbon tax among his top priorities if elected. 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. A recent poll has shown that secrets spiller Julian Assange and his WikiLeaks Party have a realistic chance of winning seats in the 78-seat Senate. Rudd was first elected prime minister in 2007, but was ousted in 2010 by his then-deputy, Julia Gillard, in an internal leadership showdown among Labor lawmakers. He was dubbed “Recycled Rudd” by the media when he reclaimed the leadership in a similar challenge on June 26 as the government faced the prospect of a loss of historic portions with Gillard at the helm. Since then, Rudd has changed several key policy positions, and opinion polls suggest Labor is closing the opposition's lead. A major policy difference is Abbott's opposition to charging polluters for their carbon gas emissions, despite Australia having some of the world's worst emission rates on a per capita basis. He has vowed to give priority to scrapping both the carbon and mining taxes. Both taxes were introduced by Labor in July 2012. The carbon tax on Australia's biggest polluters rose from AU$23 a metric ton of carbon dioxide to AU$24.15 from July 1, 2013. The opposition argues this is the world's highest tax rate on carbon dioxide and is making Australian industry uncompetitive. The tax is due to be replaced in 2015 by an emissions trading scheme, in which the cost of emitting a metric ton of carbon would be determined by buyers and sellers in a carbon market. Rudd has pledged to bring forward the emission trading scheme linked to the European market by a year to July 2014, reducing the cost to Australians of emitting a metric ton of carb dioxide from AU$25.40 to an estimated AU$6. — AP