“It’s all gone too far! All of it! It has to stop! Gabriel Sterling warned.
He cited intimidation and death threats to election workers.
Georgia is carrying out a second recount of votes at the Trump camp’s request, Joe Biden was declared a narrow winner in the key state.
Trump campaign spokesman Tim Murtaugh said it was trying to make sure that all legal votes are counted and all illegal votes are not.
“No-one should engage in threats or violence and if that has happened, we condemn that fully, he said.
It came after US Attorney General William Barr said his justice department had so far found no proof to back the president’s claims of fraud in the election, the latest setback to the Trump camp’s legal challenges in several states.
Georgia will also hold in January two run-off elections which will determine who controls the Senate.
Trump’s Republican party currently has a slim chance in the upper chamber, and a victory in the run-offs would allow it to counter the Democratic administration of President-elect Biden.
The Democrats control the lower chamber which is known as the House of Representatives.
At a news conference in Atlanta, Mr Sterling, the state’s voting systems implementation manager rebuked his fellow Republican including the president.
He said a 20-year-old contractor in Gwinnett County for Dominion Voting Systems which has become the subject of baseless right-wing conspiracy theories, had received death threats, the worker’s family was also getting harassed, Mr Sterling added.
The unnamed man had been threatened with a noose and accused of treason after transferring a report on ballot batches to a county computer so he could read it, Sterling said
Sterling said he himself has a police guard outside his home, while the wife of Georgia’s secretary of state, Brad Raffensperger, was getting sexualised threats through her cell phone.