All 22 countries covered in the poll would prefer to see Senator Obama elected US president ahead of Republican McCain.
In 17 of the 22 nations, people expect relations between the US and the rest of the world to improve if Senator Obama wins.
More than 22,000 people were questioned by pollster GlobeScan in countries ranging from Australia to India and across Africa, Europe and South America.
The margin in favour of Senator Obama ranged from 9 per cent in India to 82 per cent in Kenya, while an average of 49 per cent across the 22 countries preferred Senator Obama compared with 12 per cent preferring Senator McCain. Some four in 10 did not take a view.
"Large numbers of people around the world clearly like what Barack Obama represents," GlobeScan chairman Doug Miller said.
"Given how negative America's international image is at present, it is quite striking that only one in five think a McCain presidency would improve on the Bush administration's relations with the world."
In the United States, three polls taken since the Republican party convention ended on Thursday (local time) show Senator McCain with a lead of 1 to 4 percentage points - within the margin of error - and two others show the two neck-and-neck.
The countries most optimistic that an Obama presidency would improve relations were America's NATO allies, including Australia (62 per cent).
A similar BBC/Globescan poll conducted ahead of the 2004 U.S presidential election found that, of 35 countries polled, 30 would have preferred to see Democratic nominee John Kerry, rather than the incumbent George Bush, who was elected.
A total of 23,531 people in Australia, Brazil, Canada, China, Egypt, France, Germany, India, Indonesia, Italy, Kenya, Lebanon, Mexico, Nigeria, Panama, the Philippines, Poland, Russia, Singapore, Turkey, the UAE, Britain and the United States were interviewed face-to-face or by telephone in July and August 2008 for the poll.