"Georgia: Early voting is underway in the runoff, and we need your help to send Reverend Warnock back to the US Senate," Biden said on Twitter on Sunday.
Earlier this month, a poll by the American Association of Retired Persons (AARP) showed that Democratic incumbent Raphael Warnock had a lead of four percentage points over Republican challenger Herschel Walker (51% vs 47%) in their runoff race in Georgia.
The midterm US Senate race in Georgia will go to a runoff on December 6, while early voting will continue through Friday. The runoff comes after neither candidate managed to garner a majority of the votes during the initial election.
In the midterm elections earlier in November, Democrats defied the pollsters by managing to maintain control of the Senate while losing the House to the Republicans by a slimmer margin than expected.