The general public has a more positive take on e-voting systems than computer security specialists, according to a survey released Tuesday.

According to the study, 55 per cent of the public has a favorable opinion about e-voting but 60 per cent of security experts surveyed had an unfavorable view. While 54 per cent of the public respondents said they have confidence in the security and reliability of e-voting systems, 47 per cent of the experts said they have no confidence.

The public survey, conducted last month via the web and standard mail, counted nearly 3,000 respondents across the U.S. The survey of security specialists had a much smaller sample - about 100 respondents - and was conducted at the annual Defcon hacking conference held last week in Las Vegas. The Ponemon Institute, an independent research firm that specializes in privacy issues, conducted the survey.

"At the end of the day, our Defcon experts believe evoting is less secure than the general public. That gap exists. There could be a big surprise in our general election in November," Larry Ponemon, CEO and founder of the firm, said in a conference call with reporters.

System and programming errors topped the list of e-voting machine concerns for the experts, followed by concerns that the systems could be used to influence the outcome of an election.

Ponemon said the study shows the need for manual accountability methods until e-voting has sufficient safeguards and the need to consider the impact of abuse of e-voting records.

"I'm not trying to suggest that we have a disaster, but it's clear there are perceptions that are so different that someone should be looking at a backup plan," he said.