US Republican Mitt Romney has closed the gap with President Barack Obama and the two candidates are now tied in the Nov. 6 presidential race, according to a Reuters/Ipsos daily tracking poll released on Monday.
The online survey of likely voters found Obama and Romney were each supported by 46pc of the electorate as they prepare for their final televised debate on Monday night.
Romney trailed by 1pc point when the poll was last published on Saturday.
The two candidates have remained within three percentage points of each other since shortly after their first debate on Oct. 3.
"Today's number emphasizes the fact that the race is very close. We enter the final debate with the candidates literally neck and neck," Ipsos pollster Julia Clark said.
However, Obama still holds a substantial advantage in the battleground states that will determine the outcome of the election. Ipsos projects that Obama will carry hotly contested states such as Florida, Ohio and Virginia, for a total of 325 electoral votes to Romney's 213 electoral votes.
Reuters/Ipsos online polls are measured using a credibility interval.
The survey of 957 likely voters, conducted between Oct. 18 and Oct. 22, has a credibility interval of 3.6 percentage points.