Republican NC-9th District Congressional candidate Mark Harris answers questions at a news conference at the Matthews Town Hall on Wednesday, Nov. 7, 2018, in Matthews, N.C.

A North Carolina board ordered a new election Thursday in last year's final undecided U.S. House race after an investigation into election fraud accusations.

The North Carolina State Board of Elections voted unanimously for a new race in the state's 9th District after four days of hearings on whether to certify the result. Allegations of absentee ballot tampering roiled November's election, in which Republican Mark Harris led Democrat Dan McCready by about 900 votes.

Harris, who previously pushed for the elections board to certify the result, unexpectedly called for a new election during testimony Thursday. This week, North Carolina's elections director said operative McCrae Dowless carried out an illegal and well-funded ballot harvesting operation as he worked for Harris' campaign during the election last year.

"I believe a new election should be called," Harris said. "It's become clear to me that the public's confidence in the 9th District seat general election has been undermined to an extent that a new election is warranted."

The House did not seat Harris amid the fraud allegations. In a tweet, the elections board said it will "set the dates of the election at a subsequent meeting." It will hold new primary and general elections.

NCSBE tweet

Dowless is accused of leading an effort to illegally collect and send in absentee ballots. His workers testified that they were told to forge signatures or gather blank or partially completed ballots from voters.

In a tweeted statement Thursday, Dallas Woodhouse, executive director of the North Carolina Republican Party, said, "We support" Harris' decision and "will do everything we can to help the process and system improve in the future."

In testimony Wednesday, Harris' son, John, said he advised his father not to hire Dowless. The younger Harris does not think his father joined in the absentee ballot operation.

However, McCready's lawyers argued the testimony showed inconsistencies from statements Republican candidate Mark Harris made suggesting he was caught off guard by the concerns about Dowless. On Thursday, Harris said he believed at the time that Dowless' methods were legal.

Harris, a 52-year-old pastor, surprised incumbent GOP Rep. Robert Pittenger in a May 2018 primary. Inconsistencies in several counties — in which Harris won an unlikely proportion of absentee votes in both the primary and general elections — did not surface until after November's general election.

Democrats currently hold a 235-197 majority in the House. North Carolina's 9th District is one of three seats currently vacant.

Nonpartisan elections handicapper Cook Political Report will rate the 9th District race a toss-up, the outlet's House editor, Dave Wasserman, said.

Wasserman tweet

— The Associated Press contributed to this report

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