Cheryl Roberts was impressed with Florida's new voting machines in the 2002 primary, when she cast an electronic ballot for Democratic gubernatorial candidate Bill McBride (search). But a series of computer glitches — including startling cases of corrupted or missing data — has undermined her faith. So for Tuesday's primary in Florida, Roberts is turning to an absentee ballot so Broward County has a paper record of her vote.

"Everyone is psychologically wary of elections this year," said Roberts, a field coordinator for the American Civil Liberties of South Florida (search). "My biggest concern is whether or not voters' intentions will be counted by elections departments."

Whether paperless touchscreen voting terminals will accurately record people's votes — and whether those votes could be recounted in a close election — are open questions in Florida, epicenter of the 2000 presidential election fiasco. Polls in the crucial swing state show a dead heat between President Bush and Democrat John Kerry (search).

On Tuesday, voters in 15 of Florida's 67 counties will cast ballots on touchscreen computers that do not produce paper records of every ballot. Voters in those counties — including Broward and Miami-Dade — make up more than half of the state's registered voters.

Voter advocates promise to scrutinize election results to see if tallies match exit polls, threatening to sue over suspicious results. Computer programmers say touchscreens, which as many as 50 million Americans are eligible to use in the November election, are vulnerable to software glitches, hackers, power outages and other problems.

"I'm very worried that if the election is very, very close, the outcome will not be believed by a lot of people," said Avi Rubin, professor of computer science and technical director of the Information Security Institute of Johns Hopkins University.

More than 100,000 touchscreens have been installed nationwide, particularly in California, Maryland, Georgia, and battleground states of Florida, New Mexico and Nevada.

Gov. Jeb Bush and his top elections official, Secretary of State Glenda Hood, say touchscreens are secure and recountable. Big manufacturers such as Diebold Inc. and Election Systems & Software Inc. say touchscreens minimize errors such as overvoting, when the accidental selection of two candidates disqualifies a ballot.

Touchscreens can toggle between different languages and can be equipped with headphones, making them easier for nonnative English speakers, the illiterate and visually impaired.

"I do think that it is the best available system when you consider all the facts, including voting rights issues," said Dan Tokaji, assistant professor of law at Ohio State University.

But shocking problems have undercut attempts to promote touchscreens — once billed as the antidote to the hanging chad of Florida's outdated punch-card machines.

A study by the American Civil Liberties Union after the Democratic gubernatorial primary in 2002 concluded that 8 percent of the votes on Miami-Dade County's touchscreen machines in 31 precincts were lost.

Audit logs of ES&S machines deployed in 11 Florida counties were corrupted by a software flaw caused by low batteries. ES&S and state officials issued a software patch this summer and said the mishap wouldn't affect elections.

Miami-Dade County officials revealed last month that audit logs from the contested 2002 gubernatorial primary, first believed lost in computer crashes, were temporarily misplaced. The logs are a record of everything a machine does from the time it's turned on until it is shut off.

"We're putting all our faith in these machines to work," said Ben Wilcox, executive director of Common Cause Florida, a Tallahassee-based government watchdog group. "Florida voters suffered trauma in 2000 and basically we need to give them the confidence that that won't happen again."

For many voter advocates, the biggest worry is not election day but the prospect of a recount.

In a typical touchscreen recount, a registrar reproduces only the vote total delivered by each machine. Critics consider such numbers meaningless because they don't show whether software glitches or hacks resulted in misrecorded votes in the first place.

A voter-verifiable paper ballot, they say, is a better way to prove voters' intentions. But only a handful of touchscreens — including some in Nevada — produce paper records of every ballot.

The situation got murkier Friday in Florida, when a judge ruled that Hood's rule preventing manual recounts on touchscreen machines was against state law, which requires hand recounts in certain close elections. That could mean that touchscreens would need to be able to print paper records.

Hood was considering appealing the judge's decision, which would automatically keep the rule in place for now.

Electronic voting was hailed as the answer to the 2000 presidential election, when questions over voter intent led to recounts that lasted 36 days. President Bush won a 537-vote victory in Florida, giving him the presidency.

Gov. Bush's own Republican party recently paid for a flier criticizing the new technology and urging some voters in South Florida to use absentee ballots to make sure their vote counts. Bush defended touchscreens and said he did not endorse the mailing, which echoed Democrats and civil rights activists, who urge voters to cast paper ballots.

"The new electronic voting machines do not have a paper ballot to verify your vote in case of a recount," the flier read. "Make sure your vote counts. Order your absentee ballot today."