Two of the nation's five closest seats are in Victoria, with the battle for McEwen set to go down to the wire as voting continues into the weekend.
On Friday afternoon, the Liberals' Donna Petrovich leads sitting Labor member Rob Mitchell by just 241 votes on a two-party preferred count, with 84 per cent of the roll tallied.
There are more than 13,500 votes yet to be counted and the tally will continue Saturday and Sunday.
For now, the race in McEwen is the closest in the nation.
The other close contest is in Indi, where Liberal Sophie Mirabella is in a battle for political survival for the north-eastern Victorian seat.
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Independent Cathy McGowan leads her by 793 votes in the two-candidate preferred count, with 87 per cent of the vote counted.
There are still more than 8300 votes to be counted.
Mrs Mirabella has held the seat since 2001 and went to last weekend's poll with a nine per cent lead.
But the dynamic campaigning of Ms McGowan has placed the former spokesperson for innovation, industry, science and research in grave danger of becoming the coalition's highest-profile casualty of the election.
Mrs Mirabella this week ruled herself out of a cabinet post in the Tony Abbott government, saying her decision allowed the new prime minister to choose his ministry without waiting for the result in her seat.
The Senate vote is expected to take two to three weeks, but so far there will be two Victorian ALP senators, two from the Liberals and a likely Greens senator.
The Australian Motoring Enthusiast Party has also been slated to pick up a seat in Victoria despite only winning 0.5 per cent of primary votes in the state.
A complex system of preference flows means they could take the state's sixth upper house seat.
