Apparently, the Georgia Code Title 21 cited above relates specifically to state and local offices, and not federal offices. Information from the GA Secretary of State says the following:
Runoff elections are held when no candidate wins the required majority of votes.
Anyone who is registered to vote in Georgia can vote in state, local, and federal runoff elections. Check your voter status.
Runoff dates for the 2020 general election are:
Dec. 1 - State and local races (voter registration deadline was Oct. 5)
Jan. 5 - Federal races (Voter registration deadline: Dec. 7)
For more information about runoff elections, contact your County Registrar’s Office.
Well that would explain some of the wild rumors running around. One is that the Marxists are planning to temporarily move tens of thousands of new voters into Georgia just for the run off and another is that these two Senate seats would give Senate control to the Rats and they plan to not only remake the USA but also the Western world with total control. Therefore, no amount of money is too much to spend, not only billions but even a hundred billion or more if they can buy the state.