Researcher estimates that 15 million have already voted in the U.S.

More than 15 million of the 213 million registered voters have voted in U.S. presidential elections, according to calculations of political scientist Michael McDonald of George Mason University in Virginia.

The estimate of McDonald is based on official data of the 32 states that allow Americans to vote for early elections on November 4.

The turnout of voters in early voting system recorded so far is record, with endless queues in several states, including Florida, one of the most disputed by candidates for the White House.

According to survey released on Tuesday by the Pew Research Center, the Democrat candidate Barack Obama appears in front of the voters that have already voted, with 53% of the vote compared to 34% of Republican John McCain.

The Democrats are asking their supporters out to vote now and avoid long queues further technical problems for the day of elections.

Shadow of Bush

According to the Pew survey of the institute, the approval of President George W. Bush has fallen considerably since January and is currently at around 22%.

That sentiment would have affected so sharply the chances of McCain, that the Republican has attempted to distance himself from the president in recent weeks.

Around 47% of respondents in the survey believe that Senator McCain adopt the same model of Bush.

Obama's campaign has used this information - at all events, Obama seeks to affirm the Republican vote "will continue with the policies of Bush."

"John McCain was the co-pilot of George W. Bush when he ran the economy to the precipice," said the Democrat. "Now, you take the wheel and step on the accelerator."

The Democrat was received for a rally on Tuesday by 9 thousand people, according to organizers, despite the cold rain that fell in Chester, Pennsylvania.

"This is an incredible crowd for such a climate," said Obama. "If on election day we have that same commitment, there is no way to change not reach the United States."

Bad weather

The Republican candidate also campaigned in Pennsylvania on Tuesday but had less luck than Obama and had to cancel two acts in Allentown and Quakertown because of bad weather.

McCain managed to keep the speech planned for Hershey, which is a famous chocolate factory, along with the candidate for vice Sarah Palin.

In addition to attacking Obama for wanting to "redistribute the wealth of the country," McCain took the opportunity to try to calm down the rumors that his campaign is being undermined by criticism of Palin.

"When two individuals with their own styles come together, they not always agree on everything, but it is much more fun," he said.

McCain also said that this is not the first time that the press and the polls bet on his defeat before the hour and pledged to continue fighting until the day on November 4.