"If you wait until the weekend prior to the election to release your stink bomb, you've lost Coloradans," said George Mason University associate professor Michael McDonald, an expert in election statistics. "If you've got the game-changer, you've got to do that soon."
Offsetting that, however: Early voters tend to be die-hard partisans, whose faith in their candidate is less apt to be shaken, political researchers say. Independents and undecided voters are more likely to vote on Election Day or just before.
WHO ARE EARLY VOTERS?
Despite what you might have heard, early voters traditionally are more likely to be Republican.
Barack Obama's successful push for early votes in 2008 created the impression of a Democratic phenomenon, and that idea's been reinforced by court fights this year over changes to early voting rules in Democratic-leaning areas in Florida and Ohio.
But 2008 was an aberration, McDonald said. Obama's beefed-up early mobilizing effort benefited from infectious enthusiasm among young people and black voters for his campaign.
Across the years, early birds tend to be older and better-educated and are more likely to be white than Election Day voters, he said, and they skew toward the GOP. About a third of voters cast their ballots early in 2008, and Romney's efforts are likely to bump that up this year.
FAREWELL, ELECTION DAY?
Someday the notion of an Election Day may seem as quaint as giving a campaign speech from atop a tree stump. Maybe it'll be Election Month or the six-week Voting Season.
McDonald thinks that would be OK.
"Voters like it. They like the convenience of it," he said of early voting.
But Burden worries that something is being lost. States with tight limits on absentee voting have higher turnout rates than states with prolonged, wide-open voting seasons, he said.
That may be because in heavy early voting states, Election Day as a civic social event is disappearing.
"Before early voting took off, you could go into your workplace and see co-workers with 'I voted' stickers on their lapels. Media would be camped out at polling places. Your children's school might be a polling place. That's hard to miss," Burden said. "That energy could push over the line people who are on the edge of voting."
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