Washington, Oct 29 : A high voting percentage turnout is expected on Nov 4, as already long queues are seen outside polling booths in some states where early voting has begun. And, Democratic presidential nominee Barack Obama is leading his Republican rival John McCain''s by 53 percent to 34 percent.

According to an estimate, more than 12 million Americans across the country have already cast their ballots. In some cases, the voters waited for as long as two hours before their turn came.

In last 2004 presidential poll, 22.5 percent of American voters had cast their ballot before the election day. That is expected to rise to as much as one-third of all voters this year. “The question remains if this means a greater share of the 2008 vote will be cast early, if turnout will be up overall, or - as I suspect - a combination of these two factors are in play,” writes Michael McDonald, an associate professor of government and politics at George Mason University.

Under the early voting system in the US, 32 states allow voters to cast a ballot before the election day, either in person at the polling site or by mail. An additional 14 states and Washington DC allow it if voters can argue they will be unavailable on Tuesday, reported British English daily The Guardian.

Meanwhile, the early voting trends have gone in Democratic presidential nominee Obama’s favour. According to a poll released yesterday by the Pew Research Centre, Obama is leading 53 percent to John McCain''s 34 percent among those who have already voted.

Doug Chapin, an election expert at the Pew Centre, said: “If we’re in an election year where you have to wait two hours to vote early, you can imagine what it will look like on election day proper.”

Campaigns, voters and poll workers have enthusiastically embraced early voting. Election workers like it because the system allows them to test election procedures, affording them time to iron out flaws. It also lessens the crunch on election day.

Voters, meanwhile, welcome the convenience, and if they discover a problem with their registration, there is time to correct it and lessen the risk of being disenfranchised, Obama campaign workers say. That is increasingly vital as states enact polling place identification requirements and strictures on the voter roll. (ANI)