For further elucidation please check this:
https://ballotpedia.org/Georgia%27s_6th_Congressional_District

Republican since 1974, any win for the Dems would have been a huge upset. But even the final result narrowed down the spread in a big way.

"Ms. Handel had 51.9 percent of the vote to Mr. Ossoff’s 48.1 percent." (NYT)

Compare that with any of the margins since 1974.