WASHINGTON — The Justice Department on Friday charged a Texas man with publicly calling for the assassination of Georgia’s election officials on the day before the Jan. 6 attack on the Capitol.

The case is the first brought by the department’s Election Threats Task Force, an agency created last summer to address threats against elections and election workers. Federal prosecutors accused the man, Chad Christopher Stark, 54, of Leander, Texas, of calling for “Georgia Patriots” to “put a bullet” in a Georgia election official the indictment refers to as Official A.

Mr. Stark, according to the three-page indictment, made the admonition in a post on Craigslist, the online message board, while then-President Donald J. Trump and his allies were putting public pressure on Brad Raffensperger, the Georgia secretary of state who certified Mr. Trump’s defeat in Georgia to Joseph R. Biden Jr.

“Georgia Patriots it’s time for us to take back our state from these Lawless treasonous traitors,” Mr. Stark wrote, according to the indictment. “It’s time to invoke our Second Amendment right it’s time to put a bullet in the treasonous Chinese [Official A]. Then we work our way down to [Official B] the local and federal corrupt judges.”

Mr. Stark was charged with one count of communicating interstate threats.

The Craigslist posting came at a moment of intense political pressure against election officials in battleground states in 2020. Mr. Trump had phoned Mr. Raffensperger and demanded that he “find” nearly 12,000 votes to overturn Mr. Biden’s victory in Georgia. The next day, a Trump-inspired crowd attacked the United States Capitol in an effort to block Congress from certifying Mr. Biden as the next president.

On Thursday, a district attorney in Atlanta asked a judge to convene a special grand jury to help a criminal investigation into Mr. Trump’s attempts to overturn the 2020 election results in Georgia. If the investigation proceeds, legal experts say that the former president’s potential criminal exposure could include charges of racketeering or conspiracy to commit election fraud.

Mr. Raffensperger on Friday did not confirm if he was among the election officials targeted.

“I strongly condemn threats against election workers and those who volunteer in elections,” he said in a statement. “These are the people who make our democracy work.”

In addition to the two Georgia election officials, Mr. Stark’s Craigslist post also threatened a third Georgia official.

“milita up Georgia it’s time to spill blood,” he wrote. “we need to pay a visit to [Official C] and her family as well and put a bullet her behind the ears.”

An aide to Stacey Abrams, the Georgia Democrat who is running for governor, said he did not know if Ms. Abrams was Official C.

Mr. Stark could not be reached for comment on Friday and the identity of his lawyer was not known. He is scheduled to appear in federal court in Austin on Friday afternoon to be formally charged. He faces up to five years in prison if convicted.

Kirsten Noyes contributed research.