Leckie was born at Alexandra, Victoria and educated at Scotch College, Melbourne. He studied medicine at the University of Melbourne for two years, but after falling out with his father he prospected for gold in Kalgoorlie, Western Australia and played football in Fremantle. In 1897, he returned to Alexandra to run the family store, his father having died.
He played Australian rules football for Fitzroy Football Club (then in the Victorian Football Association) in 1895. After leaving local government in 1911, he was elected as member for Benambra in the Victorian Legislative Assembly in 1913 as a Commonwealth Liberal Party candidate. He lost his seat at the 1919 election to a Victorian Farmers" Union candidate.
He ran unsuccessfully for the state seat of Upper Goulburn in 1921 and then concentrated on his business and business groups.
In June 1941, he became Minister for Aircraft Production and held that position until the defeat of the Fadden government in October 1941. During the UAP"s term in opposition, he was deputy leader of the party in the Senate.
He lost his bid to be re-elected at the 1946 election and served out his term ending in June 1947.
During his council service, he ran unsuccessfully for the Anti-Socialist Protectionists for the House of Representatives seat of Mernda at the 1906 election.
John Leckie was a member of the Alexandra Shire Council from 1900 to 1911 and was shire president in 1904-1905. At the 1934 election, Leckie was elected Senator for Victoria as a member of the United Australia Party.
