If confirmed, Austin, 67, a retired four-star general and former head of U.S. Central Command, or CENTCOM, would be the first African American to lead the Defense Department. He was also the first Black American to lead Central Command, which oversees the U.S. military in the Middle East and parts of Africa, Central Asia and South Asia.
Austin was offered the job Sunday. He became the front-runner over the past week, but his relationship with Biden goes back years. The two spent many hours working together when Austin was running CENTCOM.
The Biden team sees Austin as someone with deep knowledge and experience at the Defense Department and believe he would be able to hit the job running once confirmed, said a source familiar with the decision process.
If he is confirmed by the Senate, Austin would require a congressional waiver to serve as defense secretary because he retired less than seven years ago. Only two other nominees have been granted such waivers, George C. Marshall and James Mattis, who served under President Donald Trump.
Asked whether the Biden team believes Austin would get the waiver, the source said it is confident that he would be viewed as a strong nominee.
As Biden continues to fill out his Cabinet, he is under pressure to name Black Americans to top posts. Biden has promised to make his Cabinet the most diverse in history.
Rep. Karen Bass, D-Calif., told CNN in an interview Sunday that Biden needed to pick Black Americans for top Cabinet positions, like defense secretary or attorney general, noting that Austin was one the top contenders backed by the Congressional Black Caucus, which she chairs.
Biden selected Sen. Kamala Harris, D-Calif., to be his running mate, and she will become the nation's first Black vice president, in addition to being the first woman and the first Asian American to hold the job.
Biden has already made several choices for Cabinet secretaries, including Xavier Becerra, who is Hispanic, for secretary of health and human services; Alejandro Mayorkas, whose parents immigrated from Cuba to the U.S., for secretary of homeland security; and Janet Yellen, who would be the first woman to hold the job, for treasury secretary. Linda Thomas-Greenfield, a Black woman, would be Biden's ambassador to the United Nations, a position that is often included in the Cabinet under Democratic presidents.
All of the nominations are subject to Senate confirmation.
Biden faces pressure, however, to select people who not only would be "accepted by all elements of the Democratic Party," as he recently said, but who also would stand a reasonable chance of getting confirmed if the Senate remains in Republicans hands after next month's runoffs in Georgia.
Austin's selection is expected to be announced in a statement Tuesday, with a public event to follow Wednesday. Biden's transition office said Monday that he would name his Pentagon chief, as well as other domestic and economic policy Cabinet nominees, by the end of this week.