California has selected its governor in an election where many cast their votes not by putting a cross on a ballot paper, or by punching holes in a piece of card, but on computerised electronic voting machines.
Critics say the ballot cast via a computer is insecure
In the wake of the fiasco in Florida during the last presidential election in 2000, these machines are seen by many in the US as a way of ensuring a fair vote. They are slowly being introduced across the nation.
They have also been used in a number of other countries including the United Kingdom, Spain, India, Australia and Costa Rica.
But some computer experts believe e-voting could actually make fraud much easier.
It is being used more and more across the US partly because of legislation called the Help America Vote Act, signed by President Bush in October 2002.
The act does not force states to switch to e-voting, but it sets standards for the conduct of elections and the maintenance of the electoral register which can most easily be met by switching to computers.
It also provides funds for states to help them make the switch.
There are several companies making these machines and they work in slightly different ways.
Typically a voter swipes a "smart card" through the machine, then uses a touchscreen to cast his or her vote.
Proponents of e-voting list several advantages: the machines can switch to a language of the voter's choice, they can easily be adapted for use by the blind, they count votes in an instant, they prevent spoiled ballots - for example, by refusing to allow the voter to select two candidates in a vote where they are only allowed to select one.
Some computer experts though are unconvinced.
The 2000 US presidential election descended into farce
One is Avi Rubin, technical director of the Information Security Institute at Johns Hopkins University in Baltimore.
Earlier this year, through a chance discovery, he was able to examine the computer programme, the source code, used in a voting machine made by Diebold, one of the largest manufacturing companies.
"The source code was very poorly written, it didn't have the kinds of controls in place that you would expect from a high-assurance system," Prof Rubin told BBC News Online.
An ordinary voter could alter the outcome of an election, he believes.
The smart card is supposed to ensure that each person votes only once.
But Prof Rubin thinks it would be easy for a computer-savvy voter to make a fake card allowing multiple votes.
"An undergraduate in my class could do it," he says.
He found that people involved in running the election could attack the system even more efficiently.
"Even more serious would be a rogue or malicious programmer working at Diebold who could put in some hidden functionality that could cause the outcome of the election to be later determined by the attacker," he says.
The Johns Hopkins team set out their concerns in a report published in July.
E-voting could mean an end to the walk to the polling station
Diebold has responded publicly to the Johns Hopkins report, though the company declined to be interviewed by the BBC.
It believes that Prof Rubin's methodology and conclusions are fundamentally flawed; along with other manufacturers, Diebold says e-voting systems are in the main secure.
And in any case, say supporters of e-voting, nothing can be completely safe.
"You're never going to secure anything totally - if someone wants to get into a bank and rob it, they're going to," says Mark Struckman, director of research at the Center for Digital Government, an independent research and consultancy firm.
"These systems though can provide electronic means to make sure that if people are hacking, you can discover that.
Mr Struckman believes that all machines should produce a "voter-verifiable paper trail" - a slip of paper which the voter can take away, like a receipt, as a record of how he or she voted.
Not all machines currently produce these paper slips; and some observers are concerned that without one, there is no record of how people voted other than what is contained in the machine's computer memory.
Another aspect of the way electronic voting is being introduced across the US which alarms some citizens is the close ties which some manufacturers have to prominent Republican politicians.
Diebold chief executive Wally O'Dell has been a major fund-raiser for President Bush.
Senator Chuck Hagel used to chair a company, American Information Systems, which made voting machines, and retains investments in the McCarthy Group, a parent company of the biggest manufacturer, Election Systems and Software.
There's no evidence that anyone has ever tried to rig an e-election, but some observers see a potential conflict of interest.
Mr Struckman however believes it is not an issue.
"If one company is fixing elections in the future, and it's because they have ties to a certain political party or not, those things will be uncovered - that company will be ruined," he told BBC News Online.
Prof Rubin, however, maintains that elections are just too important to be run on computer systems which, he believes, can never be totally secure.
He says he would be happier voting using old-fashioned pen and paper.
"As a voter I will be very disappointed if at the next election I walk into the voting booth and am presented with an electronic voting machine," he says.