Ossoff was running against Republican Senator David Perdue.
In Georgia’s other Senate runoff race, Democratic challenger Raphael Warnock defeated Republican Senator Kelly Loeffler.
The two wins essentially give Democrats control of the Senate for the first time in a decade. It also makes it easier for President-elect Joe Biden to push through cabinet nominations and legislation.
The election results have provoked whiplash in Washington which saw Republicans in November make gains in the house and hold on to Senate control.