North Carolina reporter Joe Bruno told Hill.TV on Friday that he believed Republican Mark Harris Mark HarrisTrump sparks debate over merits of voting by mail The Hill's Campaign Report: Debate over mail-in voting heats up Bevin says he lost because liberals are 'good at harvesting votes' in urban areas MORE had decided to call for a new election in his disputed House race after listening to his own son's testimony in a state hearing into alleged ballot-tampering fraud.

Harris's son had testified that he had warned his father that a political operative hired by his campaign could be engaged in unlawful work.

"I think the key moment that really struck Mr. Harris is when his son John essentially testified against him," Bruno, a reporter at WSOC-TV, told hosts Jamal Simmons and Buck Sexton on "Rising."

"They pulled up the emails that showed that John [Harris] was warning his father that [Leslie] McCrae Dowless could be operating in this illegal scheme," he continued.

The North Carolina State Board of Elections voted unanimously Thursday to call a new election in the state’s 9th Congressional District after holding an evidentiary hearing this week to look into allegations of ballot fraud in the November race.

The allegations centered on McCrae Dowless, a political operative hired by Harris’s campaign who has been accused of paying workers to illegally collect absentee ballots from voters in rural Bladen County.

Initial results from the election showed Harris leading his Democratic opponent, Dan McCready, by 905 votes.

However, the state's board of elections had refused to certify the results, leaving the race's outcome unresolved for months.

Witnesses and election officials have come before North Carolina's State Board of Elections over the past four days to describe Dowless's operation.

Bruno said Harris had likely found the evidence of potential fraud convincing.

"I think Mark Harris got to that point because he sat in that room, he listened to all of the testimony for three days, including from one woman who said she went around and collected absentee ballots, went as far as to change and trace over the ink on certain ballot envelopes, and make sure that the witness signatures had the same ink on them," Bruno said.

"There's been allegations that some votes were filled in for people when they left certain races blank, allegations that the early vote results were leaked ahead of time," he added.

— Julia Manchester