US President-elect Joe Biden speaks at The Queen theater in Wilmington, Delaware. Biden has called the violent protests on the U.S. Capitol "an assault on the most sacred of Americ...

Democratic presidential candidate former Vice President Joe Biden speaks at the Amtrak Johnstown Train Station, in Johnstown, Pa.

Supporters greet Democratic presidential candidate former Vice President Joe Biden as he steps of the train at Amtrak's Alliance Train Station in Alliance, Ohio. Biden is on a trai...

Democratic vice presidential candidate Sen. Kamala Harris, D-Calif., left, is greeted by Councilwoman Cherelle Parker during a campaign stop, in Philadelphia.

Democratic vice presidential candidate Sen. Kamala Harris, D-Calif., greets business owners and neighbors during a campaign stop, in Philadelphia.

Democratic presidential candidate former Vice President Joe Biden speaks after participating in a coronavirus vaccine briefing with public health experts, in Wilmington.

Democratic presidential candidate former Vice President Joe Biden arrives at General Mitchell International Airport in Milwaukee.

Democratic presidential candidate former Vice President Joe Biden speaks during the fourth day of the Democratic National Convention, at the Chase Center in Wilmington, Del.

In this image from video, former President Barack Obama speaks during the third night of the Democratic National Convention.

Democratic vice presidential candidate Sen. Kamala Harris, D-Calif., speaks during the third day of the Democratic National Convention at the Chase Center in Wilmington, Del.

Democratic presidential candidate former Vice President Joe Biden stands left as his running mate Sen. Kamala Harris, D-Calif., speaks at the Hotel DuPont in Wilmington, Del.

Georgia Democratic gubernatorial candidate Stacey Abrams leaves the stage after addressing supporters during an election night watch party, in Atlanta.

Democratic gubernatorial candidate J.B. Pritzker, right, and his running mate Lt. Gov. candidate Juliana Stratton celebrate as they wave to supporters after they won over Republica...

Democrat Madeleine Dean celebrates after winning Pennsylvania's 4th Congressional District race, in Fort Washington, Pennsylvania.

Former US President Barack Obama smiles as he greets Democratic volunteers in a surprise appearance in Fairfax Station, Virginia.

Former US President Barack Obama, right, greets Democratic supporters at Genesis Convention Center, in Gary, Ind. Obama rallied Democrats on behalf of Sen. Joe Donnelly, D-Ind., wh...

Former President Barack Obama, center, raises arms with Democratic gubernatorial candidate Andrew Gillum, left, and U.S. Sen. Bill Nelson, D-Fla., right, during a campaign rally in...