BBC reports that Republican Luke Letlow, 41, had been elected as Representative for Louisiana’s 5th district and was due to be sworn in on Sunday.
He announced on 18 December that he had tested positive for coronavirus and was admitted to hospital soon afterwards.
Meanwhile, Louisiana Governor John Bel Edwards ordered flags to be flown at half-mast on the day of Letlow’s funeral.
“It is with heavy hearts that @FirstLadyOfLA and I offer our condolences to Congressman-elect Luke Letlow’s family on his passing after a battle with Covid-19,” Mr Edwards tweeted.
Letlow was admitted to hospital on 19 December due to complications from the coronavirus. His condition worsened and on 23 December he was transferred to an intensive care unit at a hospital in Shreveport, where he died on Tuesday.
He is survived by his wife, Julia Barnhill Letlow, and their two young children.