Early Voting Expected to Rise in 2016 as In-Person Balloting Begins

— -- Election Day may be more than six weeks away but, starting today, some voters can cast votes at a physical polling place as statewide in-person, no-excuse voting gets underway in Minnesota and South Dakota.

With more than two-thirds of states offering some kind of early voting, the practice will trend upward in 2016, as it has in recent decades, and will play a major factor in battleground state ballots, some election experts predict.

An estimated 34 percent of voters will vote early, according to Michael McDonald, a political science professor at the University of Florida and fellow at the Brookings Institution. The steep climb in early voting has resulted from states’ making early voting more widely available, along with incremental year-to-year increases as voters become more familiar with early-vote procedures, McDonald told ABC News.

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While all states offer absentee voting, 37 states and Washington, D.C., will allow some form of early in-person voting this year before Election Day, according to the National Conference of State Legislatures. Early voting comprises both early absentee voting and early in-person voting. New York, South Carolina and Michigan are among the states that don't allow early, no-excuse voting.

Voting early offers flexibility and convenience to voters who may not be able to show up to the polls on Nov. 8, or prefer to avoid long lines on Election Day.

Whatever the motivation, early voting is likely to make up a significant chunk of the total vote in some key battleground states, Josh Putnam of the election blog Frontloading HQ told ABC News. He expects large early turnout in Florida, Georgia, Iowa, Nevada and North Carolina.

High early-vote turnout in battleground states is borne out by data from the previous elections. In 2012, early voting made up more than half the overall vote in Florida, Nevada and North Carolina. In Georgia, early voting accounted for 48 percent of the overall 2012 vote, and in Iowa that percent grew to 43 percent in 2012, up from 35 percent in 2008.

While Ohio traditionally does not have a big early vote, more than 524,000 absentee ballots had been requested as of this week, according to The Associated Press.

That marks an 8 percent increase of 40,000 compared to this time in the last presidential election. Early voting in Ohio in 2012 and 2008 comprised some 30 percent of the overall vote.

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