SIOUX FALLS, S.D. (AP) - Fewer South Dakota voters cast their ballots early in this presidential election than four years ago.

About 78,000 voters had returned mail-in ballots before polls opened Tuesday. In 2008, more than 100,000 people had cast advance votes. Last presidential election, absentee votes accounted for more than a quarter of the 380,000 votes cast in the state.

In addition to voting for president, South Dakota voters are deciding who will represent the state in its lone U.S. House seat.

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