Montgomery County mistakenly inflated its voter rolls for years, registering more than 3,000 people as independents who never meant to sign up to vote at all, officials said Friday.
The revelation - less than a week before Tuesday's primary election - won't necessarily open the floodgates to a new wave of voters. Only registered Republicans or Democrats can cast ballots in their respective primaries.
But it does explain the county's statistically improbable rise in unaffiliated voters since 2008, County Commissioner Joseph M. Hoeffel III said.
"There was no harm done here," said Hoeffel, also the head of the county's election board. "The most important thing to note is that these errors will not result in any voters being disenfranchised and unable to cast a ballot Tuesday."
Last month, The Inquirer reported on sharp increases in the number of Montgomery County voters registering without signing up as either Republican or Democrat.
Nearly half the county's 30,000 new voters since 2009 have shown up on voter rolls as unaffiliated or associated with a minor party - a good deal more than in any other county in the state.
Such voters account for fewer than 29 percent of new registrants in Philadelphia, Bucks, Chester, and Delaware Counties, according to data from the Pennsylvania Department of State.
"There's a statistical difference there that definitely seems at odds with what we're seeing in the rest of the state," department spokesman Kevin Murphy said at the time.
The vast majority of those new registrations came in through the Pennsylvania Department of Transportation's motor-voter program, a computerized system that allows users to register to vote or to update their registrations while applying for or making changes to a driver's license.
Although many initially pointed to a glitch in the system to explain Montgomery County's sudden independent wave, Department of State spokesman Ronald G. Ruman said Friday that a monthlong investigation prompted by The Inquirer's story found that "motor voter" was working fine.
Instead, he pointed at the county's Voter Services Office.
Hoeffel explained: When residents change their address for their driver's licenses on PennDot's system, they are offered the option to update their voter registration at the same time. For those already registered to vote, the process works fine, he said.
But if someone chose to update a voter card when he or she had never registered, an alert was sent to the county Voter Services Office.
Beginning in 2008, an employee there mistakenly entered those people as new registrations when they should have just been discarded, Hoeffel said. Because no party information was submitted, each of those new registrants was tagged as an independent.
Election officials were fairly certain Friday that this would not affect anyone who purposefully registered to vote as a Republican or Democrat, despite a handful of reports from some residents that they had been stripped of their party affiliation after using the motor-voter system.
"We'll get the final word after the primary," Hoeffel said.
Those who run into problems at the polls Tuesday have two options. They can come to Norristown to seek a county judge's order allowing them to vote, or they can fill out a provisional ballot at the polling place.
Voter services employees will investigate all provisional ballots after the election to determine whether they should count.
"I am confident that no voters have been disenfranchised by this error and that Tuesday's primary election will run smoothly," Hoeffel said.