This week's glitches will make voters yet even more wary of touch-screen voting, said Maryland delegate Anne Healey, who called the voting disruption a "major fiasco." Earlier this year, Healey, who is vice chairwoman of the state House Ways and Means Committee, had advocated a failed bill that would have prohibited the state from using the TSx systems because of precisely the kinds of problems that affected Montgomery County.

"It certainly undermines the confidence in the whole system," said Healey. "It does make you kind of nervous. It's a serious problem, and we need to address it."

Her district is in Prince George's County, where some polling places were unable to operate their machines because the election judges lacked the proper passwords. "I don't think we're at a comfortable level," Healey said.

Officials at the Prince George's County Board of Elections could not be reached for comment.

This situation underscores the fact that touch-screen voting is complex and is prone to these sorts of errors, according to Ion Sancho, elections supervisor of Leon County, Fla., and one of the highest-profile critics of the systems in the U.S. "The whole effort to reform our election problems [with touch-screen machines] really is a disaster," he said. Montgomery County demonstrated that running an e-voting system is too complicated for polling staffers, who are only temporary workers who participate in an election every two years, he said.