America's presidential election could be one of the closest in history, and in the past four years there has been a great deal of pressure to come up with a foolproof, electronic voting system. Ian Hardy reports on whether or not that has been achieved.
According to officials in Fairfax County, the latest e-voting technology is simple, straightforward and sure-fire.
Debate about e-voting technology may be only just beginning
The county's electoral official, Blanche Kapustin, says: "When they look at the screen they'll see that the name of the person they've selected has turned red. There's also a gigantic tick mark next to that person's name.
"They return to the summary screen, press the "next" button and once they press the "vote" button that's the end."
The data, which is collected on a memory device, is taken to a central location to be processed.
But opponents of e-voting say the current system is fundamentally flawed because there is no way that a voter's intent can ever be proved by anyone, once they have walked away from the screen.
The message is that computers cannot be trusted.
Teresa Hommel, of the website Where's The Paper?, says: "If the computers produced a verifiable paper ballot, meaning a printout that the voter would verify before leaving the booth, that then goes into a locked ballot box, and then those paper ballots are publicly counted.
"That would restore the public oversight of the election process."
E-voting machines will be used across much of the state of Maryland.
Authorities there say creating an instantaneous paper trail for the public would be logistically difficult, given that every person would have to receive a piece of paper five feet long. A recount of these strips would take months.
Linda Lamone, of Maryland State Board of Elections, adds: "Under Maryland law any voting system, or any part of any voting system, has to be tested against Federal standards.
"There are no Federal standards for printers. They're probably in development but they're not here now.
"So to install printers on this voting system would be violating Maryland law."
Historically, a paper trail is not always 100% reliable.
The "Votomatic" was at the centre of a huge controversy in Florida during the extremely close 2000 presidential election.
The voter selected a candidate by using a hole punch to push out a tiny piece of paper, called a "chad", next to the name.
Florida election officials recounted ballots looking for "hanging", "dimpled" and "pregnant" chads.
But paper is just one issue.
Maryland uses the Diebold AccuVote-TS machine, which is among the most controversial.
At one stage it was realised that the memory card inside each machine was vulnerable because the same key could be used to open any of the machines.
Tamper-free tape is now used.
One of the leading critics of Diebold is Professor Avi Rubin, of John Hopkins university, who downloaded a version of the company's machine code from the internet and analysed it for security problems.
Professor Rubin says: "We found that the way they were protecting the vote tallies on the machines was incorrect.
"The votes were stored on a magnetic card in an unprotected fashion so that anybody who had access to them could change them.
"They also implemented incorrectly the mechanism by which you can only vote once...
"It would be very easy to build smart cards that would let you vote multiple times.
"In some precincts you could get away with that because people aren't watching vigilantly."
Despite all these caveats, interest in e-voting has surged since 2002, when the states were given a use-it-or-lose-it pot of money, worth nearly $4 billion, to introduce new technology into polling booths.
Many of the people interviewed in Maryland, Virginia and Washington DC say that if you think the debate about the technology behind e-voting is spirited now, just wait until the day after the election results are announced.
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