The audit trail is required for Tuesday's primary vote to ensure that election officials adhere to a state law passed in 2005. The statute requires that the ballots of 1 percent of the votes cast in each precinct be manually tallied to ensure the accuracy of e-voting systems.

The new law expands on an earlier statute that requires voters using optical scan devices to also register their votes on paper so they can be audited. Now, all machines, including touch-screen systems, must compile a paper trail of votes.

A spokeswoman for California Secretary of State Bruce McPherson said that 37 of the state's 58 counties use touch-screen systems.

"Every voting system in California will have a paper trail in 2006," the spokeswoman said. "Voters will have the opportunity to verify their vote via a paper record, which verifies that their vote cast was indeed the vote that was recorded."

As California has moved to implement the new law, it has also been working to comply with the federal Help America Vote Act, which requires the establishment of a statewide voter registration database and that every voting precinct have a handicapped-accessible e-voting system. "These are sizeable mandates, and it is no easy task, but it is also a duty we do not take lightly," McPherson's spokeswoman said.