In late February, Mark Harris announced he will not run in the new election for North Carolina's Ninth Congressional District.
Harris said he was endorsing Union County Commissioner Stony Rushing as a candidate for his seat.
Blackwelder said in his statement he believed this is the best decision and will "hopefully prevent a run-off."
North Carolina officials set Sept. 10 as the date for the new election.
"These people need and deserve representation", Blackwelder continued.
In his post, Blackwelder said he would be refunding contributions from supporters.
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