It was the first time any Australian leader had raised such an issue in a campaign launch, and it drew prolonged applause from about 700 Labor Party faithful in the town hall at Bankstown, a working-class Sydney suburb where Mr Keating was born 49 years ago.
The occasion was as close to an old-fashioned home-town launch as it was possible to be in an age when Australian politics and elections are dominated by television - a deliberate attempt by Mr Keating to show he had not forgotten his origins at a time when unemployment of more than 1 million, 11 per cent, is at record levels.
It was also a crucial moment for Mr Keating in his bid to reverse the Labor government's decline in opinion polls less than three weeks before the election. In three main polls over the past few days, Labor trails the opposition Liberal-National coalition by between six and 12 points, enough to lose government.
At Mr Keating's request, the stage of the Bankstown Town Hall was decorated with a simple backdrop by the designer of the Australian film Strictly Ballroom, of which he is a fan.
He avoided specifics and pitched his speech at a broad vision of Australia's future, saving his call for a republic almost until the end. 'It is perhaps in part because Australians are growing in confidence that more and more of them are questioning whether it is appropriate for Australia to have as its head of state the monarch of another country,' he said. Amid a loud ovation which brought some in the audience to their feet, Mr Keating said a Labor government would appoint a committee of 'eminent Australians' to produce a discussion paper on options for a Federal Republic of Australia, with a view to putting to a public referendum the question of becoming a republic by 2001, the centenary of the states' joining in federation.
In making this a key election pledge, Mr Keating is gambling on a sense of nationalism overriding the hard economic reality which is troubling many Australians. He admitted some responsibility, as Treasurer (or finance minister) in Bob Hawke's governments, for policies which led to the recession and high unemployment. 'Governments in Australia in the Eighties were not always as prudent or wise as they should have been,'he said.
Mr Keating said unemployment was 'overwhelmingly' his principal concern but offered no new measures to relieve it. Instead, he announced Adollars 1.6bn (pounds 760m) of further assistance over three years to child and health care and the aged. He described the opposition's approach as 'the economic and social jungle of Reaganism and Thatcherism which other countries have just abandoned'.
John Hewson, the opposition leader, who will formally launch his campaign on Monday, said republicanism was not an issue and described Mr Keating's speech as 'a plea by a tired and desperate government for another chance'.