With 15 months to go before the US presidential elections, a new report has revealed that a voting machine has been found vulnerable to hacking.
The report, on optical scan voting systems, shows that the machine - one of the few in the US to have remained free of controversy - can be hacked into.
The machines are set to be used in Florida - where, seven years ago, George Bush was elected as the US president by just 537 votes amid controversy over the state's punchcard ballot system.
Last November, in mid-term elections, the result from Florida's Congressional District 13 seat was contested by the Democrat Christine Jennings, who lost the vote, when it emerged that more than 18,000 votes were lost because of what were claimed to be faulty touch-screen voting machines.
The results of the state-ordered study, carried out by scientists at Florida State University, conclude that optical scan machines - which scan in paper ballots marked in pencil by voters - can be hacked into.
The optical scan system is likely to replace the touch-screen voting machines after the state governor, Charlie Crist, signed a bill ordering them to be phased out.
Official memory cards in the optical scan machines could easily be exchanged with ones altering the vote count, the document warned.
"Specifically, it can be used to essentially swap the electronically tabulated votes for two candidates, reroute all of a candidate's to a different candidate, or tabulate votes for several candidates of choice toward another chosen candidate," it said.
In a letter, Florida's chief elections official, Kurt Browning, demanded that the machine's vendor, Diebold, deals with the flaws by August 17.
"We need to do a better job of restoring confidence to the voters," Mr Browning told Guardian Unlimited. "People are looking for the perfect voting system. And you're not going to find it." He said that, as long as humans were involved in the voting process, there would be errors.
Mark Radke, a Diebold spokesman, told the Associated Press that the deadline would be met and played down the seriousness of the report's findings. "These are not major changes, and we are confident we can meet the deadline," he said.
However, one state elections official said he retained faith in optical scan machines despite the flaws.
Ion Sancho, the supervisor of elections for Leon County, where the state capital, Tallahassee, is located, said he believed a "rigorous post-election audit" should be undertaken, no matter what technology is used.
"A voter, in his own hand, marks the ballot, and at the end of the day you have every voter's ballot," he said. "Optical scan voting technology provides hard evidence to determine whether there was fraud."
Mr Sancho, who has been an advocate of optical scan machines for years, added: "I welcome the state of Florida's reversing its position of denial and recognising that voting machines used to count votes are vulnerable. I've been vindicated to some degree."
Mr Browning said Florida would be ready for the presidential elections in November 2008. "Dealing with optical scan machines will be less chaotic than touch screen machines," he added.