iVotronic machines are used in a majority of polling places in 24 of 100 counties in North Carolina, which as 2,800 voting precincts statewide, Wright said. The other counties use the ES&S M100 optical scanning machine, he said.

Joyce McCloy, coordinator for North Carolina Coalition for Verfiable Voting, a watchdog group, said the report Wright confirmed was the only e-voting irregularity she had come across. "With new electronic voting machines, voters can obviously get nervous," she said.

Because of concerns about a repeat of problems in 2004, when several thousand votes in one part of the state were lost, McCloy's group pledged to be vigilant. "We're as busy as a one-armed man in a paper hanging contest," she said.

Tova Andrea Wang, a democracy fellow with the Washington-based Century Foundation, a non-profit public policy research institution, said that none of the problems seen so far was unexpected There have always been elections problems dating back to the turn of the century, when mechanical machines came into use because paper ballots could be easily manipulated and changed.

"There's no question that we're in a transition period" to e-voting machines, she said. Whether the system is experiencing growing pains or faces a longterm problem remains to be seen.