A spokeswoman for the California secretary of state said the Florida evaluation persuaded McPherson to sponsor a security test in his state. She said the secretary's office and Hursti are still working on the protocols and logistical details for the California test.

The spokeswoman said that a machine will be selected for the trial at random from an undetermined voting precinct in the state.

McKinney, Texas-based Diebold contends that its optical scan gear is not vulnerable to hacking and has agreed to work with McPherson on the upcoming test.

Diebold responds

A Diebold spokesman called the Leon County, Fla., hacking test invalid. "We weren't ever aware of it," he said. Hursti and Black Box were given "complete and unfettered access" to the system and the passcode, but such access isn't generally available to outsiders, he said.