The alleged problems occurred this week in Miami-Dade and Broward counties and were spotlighted in articles in the Miami Herald. Florida was the site of the notorious hanging chads that were central to the disputed presidential election of 2000. In part because of the issues in Florida that year, Congress passed the Help America Vote Act (HAVA), which, among other things, was aimed at replacing lever-activated and punch-card systems with electronic devices.

In Miami-Dade County, e-voting machines allegedly flipped candidates -- meaning the candidate chosen by a voter was not the candidate registered by the machine -- something officials denied. "I am happy to report that there are no glitches in any of the electronic voting machines at Miami-Dade early voting locations," said Lester Sola, supervisor of elections for the county. Despite the reported glitches, investigations found no problems, said Sola, who emphasized the precautions taken to ensure accurate voting.

"As a precautionary measure, if a voter makes a complaint about a particular machine, that machine is closed and sealed until a technician can assess the problem and, if necessary, take corrective action," he said. "That is what happened with two machines at early voting. After analysis, we have not found any problems with our machines. All deployed units are operational, and I can assure you that no votes were lost while assessing these units."

The voting device vendor is Election Systems & Software Inc., Sola said, adding that the system will work as planned. "We take many aggressive steps to ensure that the election is programmed and tabulated accurately," he said. "We balance the number of voters that enter a precinct to the number of ballots cast there. We also reconcile each touch-screen unit against audit data to ensure that the results are accurate."

In nearby Broward County, which includes Fort Lauderdale, similar flipping incidents were also reported on ES&S iVotronic systems. Such problems are common for at least a certain percentage of voting machines, according to Peter Corwin, assistant to the Broward County administrator.