North Carolina voters are more likely than those in other states to cast ballots in national elections without making a choice for president.
Unlike many states, a straight-party vote in North Carolina does not cast a vote for president. A ballot expert says the split makes it more likely that voters, especially new voters, will leave their polling places failing, by mistake, to vote for president.
The split between presidential and straight-party votes has brought the state national attention this year because the margin between Democrat Barack Obama and Republican John McCain is expected to be close, and North Carolina's electoral votes would be a prize for either candidate.
An unusually high percentage of people in the state who voted in the past two national elections failed to mark a presidential selection.
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In an analysis of election returns, Justin Moore, who received a graduate degree in computer science at Duke University, found that 3.15 percent of voters in North Carolina didn't vote for president in 2000, and 2.57 percent didn't cast a presidential vote in 2004.
Percentages higher than 1.1 percent -- the national, presidential-year average -- indicate a flawed ballot design or other problem, said Lawrence Norden, director of the Voting Technology Assessment Project at the Brennan Center at New York University's law school.
It is unlikely, he said, that North Carolina voters have a greater tendency than others to intentionally leave the presidential boxes blank.
"I don't believe North Carolinians are that much different from anyone else in the country," he said. "The only thing that stands out is this rule," that a straight-party vote doesn't vote for president.
The presidential and straight-ticket votes are separate under North Carolina law. In 1967, state Democrats feared the Democratic presidential candidate would be a drag on the ticket, and decided to cut the presidential selection loose from other partisan races.
In a close race, missed votes could make a difference.
In 1992, President George Bush won the state by less than 1 percent in a year in which, according to a Duke University study, about 1 percent of voters mistakenly failed to vote for president.
Johnnie McLean, deputy director of the State Board of Elections, said the ballot instructions clearly say that straight-party and presidential votes are separate.
Last week, state elections officials instructed local workers to tell voters about the need for separate votes, and sent poll workers written instructions to distribute to voters.
"We believe that the ballot is designed to comply with the law," McLean said. "I think that really what people have a problem with is the requirement that the two are separated, and we can't change that."
Norden said that he would like the law to change but that less-confusing ballots could be designed. Information about the president/straight-ticket could be higher on the ballot, and could be more clearly separated from the presidential section and the straight-party section, he said.