In the weeks leading up to the presidential election, Elizabeth Bartman and Elizabeth Weihman registered to vote as Republicans in Nether Providence Township, Delaware County officials said Monday. There was one problem: Both women had been dead for several years.

The man behind those applications, Bruce Bartman, now faces two felony counts of perjury, as well as one count of unlawful voting for successfully casting an absentee ballot for President Donald Trump in the name of Elizabeth Bartman, his long-dead mother.

Bartman was arraigned Friday and released on $100,000 unsecured bail.

His lawyer, Samuel Stretton, said the 70-year-old takes full responsibility for the crimes, and will cooperate with investigators.

“In his political frustration, he chose to do something stupid,” Stretton said. “And for that he is very sorry.”

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District Attorney Jack Stollsteimer said Bartman admitted to casting the illegal ballot to “further the campaign of Donald Trump.” But the top prosecutor cautioned that Bartman’s arrest was an isolated incident, and not an indication of larger voting problems in the county.

“For all the conspiracy theorists out there, this case today does not represent widespread voter fraud,” Stollsteimer said. “This case was evidence that one person committed voter fraud by casting an improper and illegal ballot.”

Bartman used his mother’s driver’s license to register her to vote online, and then requested and filled out an absentee ballot in her name, Stollsteimer said. He repeated the process for Weihman, his mother-in-law, using her Social Security number. The state’s system flagged the information as belonging to a dead person, but Bartman signed a letter confirming the woman was still alive.

He did not, however, cast a ballot in Weihman’s name, according to prosecutors.

Bartman’s forgery came to light gradually, investigators said Monday. Rumors began to circulate on social media that a dead voter in Delaware County had cast a ballot, and a complaint was eventually brought to the county Board of Elections.

A task force of prosecutors, detectives and other officials dedicated to investigating claims of election fraud followed up on the referral and found evidence that a crime had been committed, according to First Assistant District Attorney Tanner Rouse, the head of that task force.

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Rouse said Monday that the complaint leading to Bartman’s arrest was among a score of leads the task force followed up on during and after the election. He was adamant that party affiliation had no bearing on when or how thoroughly a tip was investigated.

“In the hundreds of calls we received and the hundreds of visits we made, we only found one instance of malfeasance, and that was Mr. Bartman,” Rouse said. “And he will be prosecuted.”

Stollsteimer’s announcement marked the third instance of reported voter fraud in Pennsylvania since the election last month.

Chester County prosecutors filed charges a week after the election against Ralph Thurman, 71, a Malvern resident and registered Republican who cast two ballots on Election Day — one for himself, and the other in the name of his son.

Donning sunglasses to hide his identity, prosecutors said, Thurman returned to his polling place in Malvern after voting once and tried to pass himself off as his son. His case is pending.

And in October, a Luzerne County man was arrested after investigators say he fraudulently applied for a ballot for his mother, who died five years ago.

Robert Lynn, 67, has been charged with forgery and interference with elections, according to court records.

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Trump’s campaign filed multiple legal challenges in Pennsylvania in the weeks since Election Day, all of which have failed.

The most recent attempt to overturn the election came Sunday, when the president’s lawyers filed a petition with the U.S. Supreme Court, asking the justices to overturn previous decisions by the Pennsylvania Supreme Court on mail-in ballots.

The petition asserts the state court overstepped its constitutional role. Those opinions, which resolved multiple cases, prohibited counties from comparing mail ballot signatures to those on file; said campaigns and political parties can’t challenge ballots as they are being processed and counted; allowed limitations on observers to the vote count in Philadelphia; and allowed ballots to count even if voters had forgotten to fill out the address or date on the envelope.