Former President Barack Obama is headlining a virtual get-out-the-vote rally on Friday with Senate candidates Jon Ossoff and Raphael Warnock to mobilize Democrats – and urge them to volunteer – ahead of the start of early voting on Dec. 14.

Obama will also highlight Monday’s deadline to register to vote in the Jan. 5 runoffs, which will determine control of the U.S. Senate. Along with the candidates, he’ll be joined at the event by Stacey Abrams and U.S. Rep.-elect Nikema Williams, the chair of the state Democratic party.

He’s expected to focus on the “high stakes of Georgia’s Senate races for the country’s future and the importance of signing up to volunteer,” according to state party officials.

The virtual rally coincides with Vice President Mike Pence’s visit to Georgia on Friday, which includes a rally in Savannah with U.S. Sens. Kelly Loeffler and David Perdue. On Saturday, President Donald Trump will campaign for the two Republicans in Valdosta.

Obama has played a prominent role in the Senate races. He held an election-eve rally in November to boost Ossoff and Warnock, and has also starred in several ads for the two contenders.