More than 10 million people cast ballots on Saturday, on top of four million who voted early.
Early results from east coast and south Australian polling booths signal a neck-and-neck race between both leading parties.
Minor party candidates are also taking seats and a hung parliament is possible.
Job is likely to improve upon the 55 seats it now holds in the lower house, after gaining seats in Tasmania and New South Wales.
Opposition Leader Bill Shorten’s claims that the government intended to dismantle Australia’s public health system, Medicare, was widely being credited with creating a late swing.
The government is polling strongly in Queensland, while Senator Nick Xenophon’s recently formed pro-protectionism party is doing well in South Australia.
Pauline Hanson’s One Nation party has also seen strong results with the controversial politician likely to return to parliament, in Queensland.
Prime Minister Malcolm Turnbull has been probably gained by the choice to leave the European Union of the UK.