SYDNEY, Nov. 6 (Saturday)--Australia began voting this morning in a historic constitutional referendum that will likely see the failure of a bid to replace Britain's Queen Elizabeth as head of state with a homegrown president.

Opinion polls, pundits and bookmakers were predicting a clear majority for opponents of the republican model, which would replace the monarch and the governor general with a president elected by a two-thirds majority of Parliament.

A survey published in the Sydney Morning Herald on Friday showed a clear majority for the "no republic" vote, even in areas previously regarded as bastions of republican sentiment. The "no" side was supported by 53 percent of respondents, while 47 percent supported the republic.

To be accepted, the proposed republic would need to attract the support of a majority of voters nationally and in at least four of the six states. That now seems an insurmountable task.

Although most voters profess some republican sentiment and almost none actively support the monarchy, the "no" camp's argument that "if it ain't broke, don't fix it," has struck home in this conservative country.

Many republicans argue that an elected president would be little different from the status quo, under which the governor general is appointed by the queen on the prime minister's recommendation.

If the republicans win, the queen and governor general would be replaced by an Australian president on Jan. 1, 2001, the 100th anniversary of the proclamation of the Australian commonwealth. The only other change of note would be the eventual removal of the queen's likeness from Australian coins.

The issue has failed to capture the public imagination, due partly to widespread skepticism toward the political establishment and the fact that the debate was initially eclipsed by Australia's involvement in the East Timor crisis.

If the republic question is defeated, it will be despite strong support for the "yes" campaign from a raft of television and sports celebrities and almost universal backing from the Australian media.

One newspaper, The Australian, put a picture of a "yes" campaign banner and an editorial arguing strongly for a pro-republic vote on its front page today.

Other newspapers are making a link between the referendum and Australia's participation in the rugby world cup final against France in Cardiff, Wales, later today.

"For many, there is a delicious prospect that up against a team from France's Fifth Republic, the Wallabies might well be the first national team to triumph from Australia's First Republic-elect," said Saturday's Sydney Morning Herald.