(CNN) -- More than two million Americans have already cast ballots for president less than three weeks before Election Day with a substantial number coming in the battleground state of Iowa. The state, which holds six key electoral votes, is on pace to exceed the 1.5 million votes cast early in 2008 -- a trend that is not lost on either political party. While both parties are investing resources in early voting, Democrats' push to turn out voters -- and in particular young voters in Iowa -- could be paying off. Early numbers, which are updated daily, show that almost 20% more registered Democrats than registered Republicans have voted so far.
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Of the two million ballots cast early, a quarter of a million were cast in Iowa
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Trends show registered Democrats voting early more than Republicans in Iowa
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Republicans could close the gap in Iowa with strong Election Day and early voter turnout
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Up to 40% of eligible voters could cast their ballots early in 2012
Republicans
Republicans
Of the 463,219 early voting ballots requested in the state as of Thursday morning, 45% came from registered Democrats compared to 30% of registered @placeholder.
Election Day
Election Day
That's assuming that @placeholder returns mirror 2008 as well.
Republicans
Republicans
"If you paint it with a broad brush, a lot of Democrats vote absentee, @placeholder go to the polls.
Iowa
Iowa
Iowa
Iowa
Iowa
What's also different is the way that states collect data, meaning that it is easier to infer conclusions from returns in states that report party registration, like @placeholder.
Iowa
Iowa
Iowa
Iowa
Iowa
• @placeholder (September 27): Of the almost 450,000 absentee ballots requested, more than half have been returned.