State Dept. condemns arrests, repression in Russia

In one of her first official acts as vice president, Harris administered oaths of office to her successor from California and the winners of the Georgia Senate runoff races -- giving the Democrats control of the Senate.

Sen. Alex Padilla, the former California secretary of state nominated to the Senate by Gov. Gavin Newsom, will serve out Harris' vacated term as the state's junior senator.

After winning the contentious Georgia Senate runoff elections on Jan. 5, Sens. Jon Ossoff and Raphael Warnock give Democrats the majority in the Senate as they seek to carry out Biden and Harris' new agenda.

Following the swearing-in of the three senators, it is expected that Sen. Chuck Grassley, R-Iowa, will be designated as president pro-tempore emeritus and Sen. Patrick Leahy, D-Vt., will be elected as president pro-tempore of the Senate. Later, the body is expected to appoint secretaries for the majority and minority.

With the Senate split 50-50 between Democrats and Republicans, Harris will likely need to cast tie-breaking votes in the body.

Closing out the inaugural parade, Vice President Kamala Harris -- the first woman, first Black woman and first South Asian American to serve as the country’s second in command -- and husband Doug Emhoff -- the nation’s first second gentlemen -- were escorted in their first walk onto the White House grounds by the Howard University Showtime Marching Band.

As ABC News Chief White House Correspondent Cecilia Vega and other reporters shouted questions at Harris as she walked by to enter the Eisenhower Executive Office Building next door where the vice president's office is located, she was asked, “What’s your first job?" 

"Walking to work," Harris replied, accompanied on that first walk by Howard's marching band.

Harris, a proud alum of Howard University, is also the first graduate of a historically Black university in the White House.

She made her Howard education a central part of her campaign for president and nodded to her "HBCU brothers and sisters" when accepting Biden's offer to join him on the now-winning ticket.

Later on in the day, Harris will return to Capitol Hill to swear in Sens.-elect Jon Ossoff and Raphael Warnock of Georgia and her successor, Alex Padilla of California -- triggering Democrats taking the majority in the Senate where Harris will cast tie-breaking votes as Senate president.

Biden, for the first time as the 46th president of the United States, has arrived at the White House, his expected home for the next four years. He held hands with the first family, all donning masks, as they walked the final blocks.

As they walked through the northwest gate, a reporter asked what his message was to the world, and Biden replied, "Unity."

A U.S. Army band played "Hail to the Chief" as Biden and Jill Biden stood in front of the North Portico doors. The couple embraced before the rest of the first family joined them, and together, they walked inside the White House.

The day's inaugural ceremonies are set to continue into the night.

Biden is slated to sign executive orders in the Oval Office Wednesday evening and swear-in Day One appointees in a virtual ceremony. Biden and Harris are then scheduled to deliver remarks before 9 p.m. during the "Celebrating America" inaugural program and close the night out with a wave to the nation from the Blue Room Balcony.

Unlike previous administrations, Biden comes into office without any of his Cabinet nominees confirmed. As he enters the White House, his nominees enter Day One performing in an acting capacity.

As Biden and Harris receive their first presidential escort to the White House, they're surrounded by a fortified Washington, D.C.

At least 25,000 National Guard members are in the District to safeguard the inaugural ceremonies after a seige on the U.S. Capitol two weeks ago heightened security concerns.

And at least a dozen Army National Guard members were removed from the inauguration security mission this week, including two members who were sent home after vetting uncovered extremist links, a Pentagon official said Tuesday.

-ABC News' Luis Martinez