Transcript for Election fraud scandal brings new election in North Carolina

that bombshell development in North Carolina tonight. There will be a new election. State officials ordering that election in a congressional race amid sweeping allegations of tampered ballots. The Republican who appeared to win by less than 1% was brought to tears after his own son said. And then today, that candidate suddenly calling for a new election himself. Here's ABC's Mary Bruce. Reporter: After days of dramatic testimony about his campaign's alleged election fraud, tonight, a stunning announcement from Republican candidate mark Harris. Through the testimony I've listened to over the past three days, I believe a new election should be called. Reporter: At the center of the controversy, Harris's political strategist mccre Dowless. Accused of tampering with more than 500 absentee ballots to help Harris win. The election decided by fewer than 1,000 votes. Democrat Dan Mccready conceded, but one month later, with questions growing, he took it back. I didn't serve overseas in the Marine Corps just to come back home and watch politicians and career criminals attack our democracy. Reporter: Our Steve osunsami caught up with Dowless, who refused to testify without immunity. What do you say to people who say that you rigged this election? No comment. Reporter: At the board of no red flags, but his own son testified that he warned his father that Dowless was "Shady." I love my dad and I love my mom. Okay? I certainly have no vendetta against them. No family scores to settle. Okay? I think that they made mistakes in this process. Reporter: His testimony bringing his father to tears. Today, Harris admitted his son was right, but said at the time, he didn't take him seriously. I'm his dad, I know he's a little judgmental and has a little taste of arrogance. Reporter: And then this surprising twist. I've experienced two strokes from which I'm still recovering. And I struggled this morning with both recall and confusion. Reporter: Harris then calling for North Carolina voters to get a do-over. And late tonight, the board of elections voted unanimously to call for that new election, but we don't know yet exactly when that will be. And tonight, despite our repeated requests, it's unclear whether mark Harris will be on that ballot. David? All right, Mary Bruce live from the hill tonight. Mary, thank you.

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