Printing mistakes will force local election officials in Pennsylvania and Oregon to redo thousands of mailed ballots, a laborious process that could delay results for some closely contested races in Tuesday’s primaries. In Pennsylvania, officials in Lancaster County said the company that printed its mailed ballots included the wrong ID code which is preventing scanning machines from being able to read them. In Clackamas County, Oregon, about half the ballots sent to voters included a blurry bar code that cannot be read by ballot-scanning machines. Oregon and Pennsylvania are among five states holding primaries this week.

Printing mistakes will force local election officials in Pennsylvania and Oregon to redo thousands of mailed ballots, a laborious process that could delay results for some closely contested races in Tuesday’s primaries.

In Pennsylvania, where GOP primaries for governor and U.S. Senate are drawing national attention, officials in Republican-leaning Lancaster County said the company that printed its mailed ballots included the wrong ID code, preventing scanning machines from being able to read them. The problem involved at least 21,000 mailed ballots, only a third of which were scanning properly.

The glitch will force election workers to hand-mark fresh ballots, a process expected to take several days. Officials in the county, the state’s sixth most populous, pledged that all the ballots will be counted eventually.

“Citizens deserve to have accurate results from elections and they deserve to have them on election night, not days later,” Josh Parsons, a Republican and vice chair of the county board of commissioners, said at a news conference. “But because of this, we’re not going to have final election results from these mail ballots for probably several days, so that is very, very frustrating to us.”

In Berks County, Pennsylvania, a judge ruled Tuesday that all polling places would remain open an hour later, until 9 p.m. Eastern, after several locations experienced technical issues with electronic pollbooks that are used to check in voters. Voters who arrive at polling places after 8 p.m. will have to cast provisional ballots rather than using voting machines.

The problems in Pennsylvania flared in a state where former President Donald Trump disputed his loss to Joe Biden in 2020 and where many Republican lawmakers have repeated his false claims of a stolen election.

The wrongly coded mail ballots drew renewed attention to a 2019 state voting law — passed with bipartisan support — that greatly expanded voting by mail, a frequent Trump target.

Local election officials throughout the state have criticized several of the law’s restrictions, especially one that prevents them from processing mailed ballots before Election Day. That would allow counties to get a head-start on validating those ballots and start identifying any errors.

The Lancaster County board chairman, Ray D’Agostino, called the law “untenable” for counties trying to run elections.

County officials said the contractor, Claysburg, Pennsylvania-based NPC, sent the county test ballots with the correct ID code, but used the wrong code on the ones sent to voters. NPC did not immediately respond to a message seeking comment, but D’Agostino said the company had taken “full responsibility.”

The Pennsylvania Department of State said it was aware of the problem in Lancaster County. Spokesperson Ellen Lyon said no other counties have reported similar issues.

In McKean County, Elections Director Lisa Pratt said ballots are printed in-house, and there were no issues.

Lancaster County election workers now must recreate voters’ choices on blank ballots and then scan those, a process expected to start Wednesday. Lancaster County, which went for Trump by about 16 percentage points over Biden in the 2020 presidential contest, had to use a similar process during primaries last year because of a printing error by a different vendor that was later fired.

Christa Miller, chief clerk of voter registration, said an elections worker will read out each voter’s choices, a second worker will record them on a blank ballot, and an observer will make sure the choices are marked correctly.

“Our main priority is accuracy and not how fast we can do something,” she said.

Associated Press writers Gillian Flaccus in Portland, Oregon, and Chris Grygiel in Seattle contributed to this report.

In Oregon, where all registered voters receive a mailed ballot, officials in one politically pivotal county are dealing with a similar problem. About half the ballots sent to voters in Clackamas County, the state’s third most populous, included a blurry bar code that cannot be read by ballot-scanning machines.

Teams that include both Democrats and Republicans are duplicating every ballot so they can be scanned. Ben Morris, a spokesman for the secretary of state’s office, said the results could be delayed but will be accurate.

Pennsylvania and Oregon were among five states holding primaries Tuesday, along with Idaho, Kentucky and North Carolina, where election officials were investigating delays at polling places in three counties. Voting hours might be extended if any voters had been unable to cast a ballot, said Karen Brinson Bell, executive director of the North Carolina State Board of Elections.