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Incumbent party leader Harold Holt sensationally disappeared while swimming at Cheviot Beach near Portsea on the Mornington Peninsula of Victoria on 17 December 1967. William McMahon, the incumbent Deputy Leader of the Liberal Party was assumed to be his probable successor, however, John McEwen, the interim Prime Minister and leader of the Country Party (the junior Coalition partner), announced that he and his party would not serve in a government led by McMahon. McMahon subsequently withdrew. McEwen himself had been encouraged to remain Prime Minister on a more permanent basis but to do so would have required him to defect and lead the Liberals, an option he had never contemplated.
John McEwen, interim Prime Minister. Although leader of the Country Party, McEwen was encouraged to stay on a Prime Minister on a permanent basis which would have required him to defect and lead the Liberals, which he wasn't willing to do.
McMahon was re-elected unopposed as deputy Liberal leader. To date, Gorton is the only Australian Senator to be sworn in as Prime Minister; he would subsequently win Holt's vacant seat of Higgins at a by-election. Hasluck was later nominated and accepted the position of Governor-General from Gorton in 1969 and Snedden became party leader in December 1972. Bury later served as Treasurer of Australia under both Gorton and McMahon.
See also
Other leadership ballots held following the death of a prime minister: