Republican Mark Harris will not run in a special U.S. House election in North Carolina brought about by allegations of election fraud against an operative his campaign employed last year, he announced Tuesday.

The pastor cited his health in declining to run for Congress again in North Carolina's 9th District. Harris said he has a "necessary surgery" scheduled in March. He has suffered from health issues, including a blood infection in January. Harris appeared weary during four days of hearings last week on voting irregularities.

"Given my health situation, the need to regain full strength, and the timing of this surgery the last week of March, I have decided not to file in the new election for Congressional District 9," he said in a statement Tuesday.

Democrat Dan McCready, who trailed Harris in November's general election before the state ordered a new race, has already declared his candidacy in the special election. The North Carolina State Board of Elections has not yet set new dates for primary or special elections. The 9th District race is the country's last undecided House contest from last year.

The accusations of absentee-ballot tampering against McCrae Dowless, who worked for the Harris campaign, could have dragged on the pastor's campaign in a new election. In announcing he will not run, Harris endorsed Union County Commissioner Stony Rushing for the seat.

The nonpartisan elections handicapper Cook Political Report considers the district a toss-up.

The state elections board unanimously ordered a new election on Thursday. Earlier that day, Harris surprisingly called for another race after his lawyers argued North Carolina should certify his victory. It followed testimony from Harris' son, who said he warned the candidate against hiring Dowless.

"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 elder Harris said on Thursday.

The North Carolina race has reignited conversation about fraud in U.S. elections. Asked about the North Carolina race last week, Trump said he condemns fraud "of any kind, whether it's Democrat or Republican." He again pointed, without evidence, to a claim that a "million fraudulent votes" were cast in California.

Senate Majority Leader Mitch McConnell used the North Carolina race to criticize Democrats on Tuesday. He conflated the election fraud allegations against Dowless — which involved people who work for him collecting and sending in empty or incomplete absentee ballots — with fraud carried out by the voters themselves.

"We were hit with left-wing talking points insisting that voter fraud wasn't real. 'Never happens,' they said. That fraud just didn't happen," McConnell said. "That modest efforts to ensure that voters are who they say they are and are voting in a proper place were really some sinister right-wing plot to prevent people from voting."

Democrats have indeed criticized Republican voter identification efforts as an effort to disenfranchise Americans, particularly minority voters. A federal appeals court struck down one GOP voter identification law in North Carolina in 2016, which it said would "target African-Americans with almost surgical precision." The Supreme Court declined to reinstate it in 2017.

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