Now that the dust has settled from the general election and the U.S. Senate runoff election in Georgia, there is no doubt that the 117th Congress will have the closest partisan balance in modern history.
In the House, Speaker Nancy Pelosi will have the slimmest majority in recent times, with a 222-211 spread (currently with two vacancies). In the Senate, there is a 50-50 split between parties, with the vice president casting the tiebreaking vote.