Biden Transition Updates

Arizona Secretary of State Katie Hobbs and Gov. Doug Ducey exchange election documents as they certify election results Monday at the Arizona Capitol in Phoenix. Ross D. Franklin/AP hide caption

President-elect Joe Biden has nominated labor economist Cecilia Rouse, seen here in 2016, to head his Council of Economic Advisers. Mel Evans/AP hide caption

Neera Tanden, president and CEO of the Center for American Progress, speaks at a forum on wages and working people on April 27, 2019. President-elect Joe Biden is nominating Tanden to run the Office of Management and Budget. Ethan Miller/Getty Images hide caption

The Pennsylvania Supreme Court on Saturday rejected a lawsuit by Republicans challenging the state's mail-in voting law. Mary Altaffer/AP hide caption

An election official pauses during the ballot recount earlier this month at the Wisconsin Center in Milwaukee. After recounts in Milwaukee and Dane counties, President-elect Joe Biden narrowly increased his winning margin over President Trump. Scott Olson/Getty Images hide caption

President Trump took questions for the first time since he lost the election to Joe Biden after he spoke to troops serving overseas on Thanksgiving. Andrew Caballero-Reynolds/AFP via Getty Images hide caption

President-elect Joe Biden on Tuesday in Wilmington, Del., where he named John Kerry as a climate envoy. He says he'll also appoint a domestic climate policy coordinator to push for action across the government. Carolyn Kaster/AP hide caption

President-elect Joe Biden delivers a Thanksgiving address Wednesday in Wilmington, Del. Mark Makela/Getty Images hide caption

Then-Vice President Joe Biden gestures toward Chinese President Xi Jinping and his wife Peng Liyuan during an arrival ceremony in Andrews Air Force Base, Md., Sept. 24, 2015. Carolyn Kaster/AP hide caption

President-elect Joe Biden on Tuesday introduced his nominees and appointees to key national security and foreign policy posts. In an exclusive interview with NBC News' Lester Holt he said key agencies from the Trump administration are reaching out to facilitate the transition of power. Carolyn Kaster/AP hide caption

President-elect Joe Biden addresses reporters Tuesday in Wilmington, Del. Chandan Khanna/AFP via Getty Images hide caption

Michigan Attorney General Dana Nessel announced Tuesday her office is investigating threats against members of the Wayne County Board of Canvassers. Nessel seen above in March during a news conference in Lansing, Mich. David Eggert/AP hide caption

An election worker talks with a colleague during ballot counting Nov. 6 in Philadelphia. Pennsylvania certified its election results on Tuesday. Chris McGrath/Getty Images hide caption

President-elect Joe Biden introduces key foreign policy and national security nominees and appointments Tuesday in Wilmington, Del. Mark Makela/Getty Images hide caption