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."
"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.
Latest economic figures show a sharp decline in the nation's finances, with the Treasury Department on Friday 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, reveals a substantial deterioration in Australia's finances since May, when the department forecast a deficit of AU$18 billion.
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 latest figures show the Australian jobless rate crept from 5.6 percent in May to 5.7 percent in June.