An Australian on Tuesday bet 50,000 Australian dollars (40,000 US dollars) on Barack Obama winning the November US presidential election.

 "Until the last week, the money was fairly evenly split between McCain and Obama, but it has been all one-way traffic this week, with punters jumping off the McCain train," Sportingbet Australia chief executive Michael Sullivan said.

 A poll last week by the private-sector think tank the Lowy Institute showed almost three-quarters of Australians keen on an Obama victory.