DENVER -- Thirteen Colorado voters who claim unsecure electronic voting machines threaten the integrity of elections will ask a judge to bar their use in November.

The voters filed a lawsuit alleging the state failed to do legally required tests on the machines.

"People were needed to stand up and say there's a problem with our election system and we need to fix it," said Arapahoe County voter Rochelle Dworet Cohen.

The state employee who conducted at least some of the tests said in a recently released deposition that he had no formal training in computer science.

Critics said the systems are prone to breakdowns and vulnerable to computer hackers. One hacker reportedly penetrated a machine's software in less than a minute.

"The tampering that can be done is completely undetectable, and in fact these malicious software programs can erase themselves after they finish doing their dirty work," said Voter Action co-director Lowell Finley.

Kristen Holtzman, spokeswoman for state Attorney General John Suthers, said there are safeguards to protect the voting machines and election results.

The machines were used in some counties during the August primary election with few, if any, problems.

"We have done a lot of testing and feel quite secure with its accuracy," said Adams County clerk and recorder Carol Snyder.

"The machines provide as much security as any other voting method," said Holtzman. The two candidates for Colorado secretary of state said more work needs to be done.

"We've rushed to get them into this election without doing the proper testing, and the Secretary of State is supposed to do that and she still needs to do that," said Ken Gordon, Democratic secretary of state candidate.

"Testing ought to occur before the election; testing ought to occur after the election. Testing ought to be continuous in terms of making sure these machines accurately count every vote," said Mike Coffman, Republican secretary of state candidate.

The case goes to trial Wednesday in Denver District Court.

Federal law requires each county to have at least one electronic voting machine for disabled voters.