Potential nominees are in ABC order.
Stacey Abrams
Stacey Abrams was the Democratic nominee for Governor in Georgia back in 2018. She lost to Brian Kemp by just over 50,000 votes. Abrams didn't concede and claimed the Kemp was intentionally barring certain groups from voting. Abram has never held national officer or statewide office, only being a state representative. Critics say she isn't experienced enough, but Biden has said he could see her as his VP.
Tammy Baldwin
Baldwin is currently a senator from Wisconsin. She is more progressive than the moderate wing of the party and she is the first LGBTQ woman to be in the senate. Baldwin comes from a state that Trump won in 2016, and she recently won re-election in 2018. Baldwin would become the first gay vice presidential nominee ever.
Catherine Cortez Masto
Cortez Masto currently is a Senator from Nevada. She is the head of the powerful Democratic Senatorial Campaign Committee. What does that mean? She brings a large list of donors and fundraisers who can donate cash to the Biden campaign. Cortez Masto is also latina. This could help Biden with a group he underperformed with during the Democratic Primary.
Kamala Harris
Pundits seems to think Harris will be Biden's pick for VP. Harris is a Senator from California and ran for President during the primary season. She comes from a large Democratic state and has ties between the moderate and progressive wings of the party. Harris proved to be a strong debater and comes from a wealthy Democratic donor state.
Amy Klobuchar
Senator Klobuchar dropped out and endorsed Biden right before Super Tuesday. She is currently a Senator from Minnesota and comes from the more moderate portion of the party. She comes form a midwestern state the Trump nearly won, so she might have the touch to get voters in the Rust Belt to voter for Biden. She had some strong performances in debates and can gold her own.
Elizabeth Warren
Elizabeth Warren ran for the Democratic nomination as well during the primaries. Warren is younger than Biden, but is still 70 years old. She is more progressive than Biden as well, and something she would balance out the ticket between the moderates and the progressives. Biden might choose her to get more progressive voters.