"The 2002 primaries in Florida were a pretty jarring example of what can happen if a new voting system is put in place in an abbreviated timetable where neither voters or workers have had enough training," he said. "From the moment the polls opened, you could tell it was going to be a bad day."
In Southeastern Pennsylvania, Bucks, Chester and Delaware Counties have new systems; while Philadelphia and Montgomery County are upgrading existing machines.
Pennsylvania League of Women Voters member Lora Lavin, who helped write the state plan for implementing the federal law, said she was concerned that Pennsylvania was "heading for a train wreck."
"I hope that's not the case," she said.
But Pennsylvania Elections Commissioner Harry VanSickle is confident things will go smoothly. The state has launched an interactive voter-education Web site to complement efforts under way in the counties, he said.
"We feel the training at the county level is going very well," VanSickle wrote in an e-mailed statement. "The vendors are conducting a lot of training with county officials who are training district election officials."
Also, voter turnout is expected to be light. There is only one statewide primary contest for federal office - the Democratic nomination for U.S. Senate - and local races typically attract fewer voters.
The new voting systems are mandated by federal rules that require blind and handicapped people to be able to vote independently, and voters to be able to correct a ballot if they make a mistake. However, none of the systems produce a separate piece of paper that would show voters their completed ballot and be available for recounts.
The state's counties will use 11 different voting systems produced by six manufacturers. The two most common are Elections Systems & Software of Omaha, Neb., supplying systems for 36 counties, and Diebold, supplying 16 counties. Philadelphia uses machines from Danaher in Washington, D.C.
So far this year, some problems introducing new machines have been reported in Texas and Cook County, Ill., but none threatened to overturn election results, Seligson said.
Chester County is using new machines but hasn't yet started a public rollout of the two new systems voters will face. Officials are training poll workers.
The county will use an optical-scan system that requires voters to cast ballots by filling in circles next to candidates' name. The county is buying 230 dozen marking pens and 290,000 ballots printed on special, coded paper that is fed into a scanner.
Chester County is also getting one touch-screen machine for each of its 223 precincts to meet accessibility requirements.
Linda Cummings, county director of voter services, said a public education campaign would start next week with machines set up in senior centers, malls and libraries.
In contrast, Delaware County is in the middle of an ambitious public demonstration schedule of its new electronic machines.
Officials are training the county's 1,800 poll workers. They're asking the handicapped to try out the machines, and they have a crew of technicians who will be on call Election Day.
Last week, Rob Powell got his first taste of what it will mean to vote without anybody helping him.
Powell, 57, of Chester, was at the Center for the Blind and Visually Impaired trying out the new machines, and despite some problems with casting a write-in vote, he gave the system a qualified passing grade.
"Even if you don't know braille, it was easy," he said. "It takes 20 to 25 minutes to vote but it is worth it for the independence factor."
Delaware County executive Marianne Grace said the test runs had provided valuable feedback on problems that need to be fixed before Election Day - particularly the inability of voters like Powell to cast write-in ballots.
Joseph Passarella, Montgomery County director of voter services, said the county expected to have upgrades for about half of its 1,050 Sequoia machines by tomorrow. Training sessions for poll workers start Wednesday.
Because those machines have been used for a decade, voters will see little change when they go the polls, Passarella said.
In Bucks County, officials have learned its supplier couldn't deliver in time, so county officials decided to keep the old lever machines.
But under federal rules, the county may forfeit nearly $1 million in federal aid and leave election results open to legal challenges. It also risks penalties from the U.S. Department of Justice.
Justice department spokesman Eric Holland said the agency evaluates each situation separately.
Bob Lee, who oversees voter registration for Philadelphia, said the city had used Danaher machines for the last six elections.
"All the machines have been upgraded, the machines were unit tested, the system was tested - we're ready to go," he said.
In Allegheny County, officials have launched a last-minute blitz to educate voters about the new machines, despite a lawsuit seeking to prohibit them . A hearing on that case, which could have statewide repercussions, is set for Tuesday.
Doug Hill, executive director of the County Commissioners Association of Pennsylvania, was optimistic.
"It is good we can give everybody a trial run in the primary, he said. "We will be more prepared for the general."
Contact staff writer Nancy Petersen at 610-701-7602 or firstname.lastname@example.org.