Australia's opposition Labor Party on Saturday claimed the government had lost its mandate to rule, after national elections failed to give Prime Minister Malcolm Turnbull an obvious victory.

Nearing midnight on Saturday, Turnbull's Liberal/National government was unable to claim a win in the election they called early, with the prospect of a hung parliament looming as ballots were counted late into the night.

Labor leader Bill Shorten, who campaigned hard on health and education in a pitch directed at low and middle income earners, said that after his party suffered a thumping defeat in the last election in 2013, it was "back".

"Three years after the Liberals came to power in a landslide, they have lost their mandate," he told cheering supporters in Melbourne.

Analysts have suggested that neither Labor or the Liberal/National coalition have won the 76 seats needed to form a majority in the 150-seat House of Representatives.

While the coalition appears ahead of Labor in the count, it is expected to need the support of at least some of the likely five independents and minor parties in parliament to form a government.

An upbeat Shorten said that however the vote worked out, "Mr Turnbull will never be able to claim that the people of Australia have adopted his ideological agenda".

"He will never again be able to promise the stability which he has completely failed to deliver tonight."

The former union leader conducted a strong campaign, pledging to improve health and education spending, encouraging more renewable energy and a fairer tax system.

"We are the party that includes every citizen of the great Australian aspiration for the fair go all round," Shorten said, using a common Australian expression for equal opportunity.

"And we are the party for the people whose voices all too often go unheard."

"And I in particular tonight, I say to all those Australians who feel marginalised and forgotten -- alienated and excluded -- and to all those Australians who feel that politics as usual simply doesn't work for them. Labor will not leave you behind. We will not let you down," he said.

Turnbull called an election early because crossbenchers hold the balance of power in the upper house Senate.

They have failed to pass deadlocked legislation to overhaul unions, providing the trigger for a double dissolution of parliament, where all seats in the upper and lower houses are contested.