"The percentage of registered voters casting ballots this year is projected at 60.7 to 61.7 percent, according to the center -- a figure much lower than the modern-day record set in 1960 -- 67 percent.

Democrat Barack Obama's campaign is credited with building a sophisticated organization at local levels in key states that energized voters to register and to stand for hours in line to cast early ballots.

Nationwide, early votes totaled at least 31.7 million in at least 30 early voting states, said Michael McDonald, a professor at George Mason University.

McDonald, who also produced projections of voter turnout, estimated Friday that 130.9 million ballots were cast by 61.5 percent of Americans who were eligible to vote. The final tally is expected to be counted by early December, he said."