It could take more than a week to learn who will govern Australia as the country's two main parties start wooing independent lawmakers after an inconclusive election.
Prime Minister Julia Gillard says she will remain the nation's caretaker leader during the "anxious days ahead" as vote-counting continues.
The Australian Electoral Commission website said early on Sunday that centre-left Labor and the conservative Liberal Party-led coalition each had 71 seats, meaning neither could achieve the 76-seat majority.
Liberal leader Tony Abbott said he would immediately begin negotiations with independents to form a government.
The ranks of the independents in the 150-seat lower house rose from two at the last election to three, possibly four, this time around.
Two independents, Rob Oakeshott and Tony Windsor, said they would side with whichever party could provide the most stable government
The election results were expected to be the closest since 1961, when a Liberal government retained power with a single seat.
Parliamentarian Andrew Robb said his Liberal party will be able to govern immediately, accusing Labor of being "a recipe for instability and division."
His counterpart Labor's Bill Shorten said the independents will be negotiating with both leaders.
Pundits said Australia's major foreign policy positions, including its deployment of 1,550 troops to Afghanistan, would be unaffected by whichever party wins because both hold similar views.
Domestic issues vary across the large and diverse country, including hot topics such as asylum seekers, healthcare and climate change.
Markets are expected to react negatively to the results at the opening on Monday.