In the last presidential primary debate, Joe Biden stunned everyone by announcing that his running mate will be a woman. It’s unprecedented for a leading candidate to bind themselves with such a commitment on the choice of running mate. Ted Cruz did announce a running mate, Carly Fiorina, during the Republican primary in 2016 but that was more of a Hail Mary pass. Suburban and black women were key to Democratic party's success in 2018 mid-terms and Biden will hope to strengthen his appeal to this vital constituency.
What explains this outsized representation for senators as VP picks? Firstly, many of the presidential candidates have been senators (Hillary Clinton, Barack Obama, John Kerry, Al Gore and the list goes on) and it’s only natural for them to have picked someone whom they knew well and had worked alongside. In fact the last Democrat ticket to not feature any US senator was in 1945 with FDR and Henry Wallace.
Secondly, the Senate has a majority requirement of 60 votes out of 100 and requires consensus building for any legislative measure to succeed whereas the House only requires a simple majority to see a bill through. A senator as VP could use their understanding of the Senate and leverage past relationships to drive the administration’s legislative agenda. The Senate also has sole authority to confirm a president’s nominees to the cabinet, judiciary and key executive positions. For a president to have their nominee rejected by the senate is an embarrassment and a senator turned VP can go a long way in ensuring senate confirmations.
Thirdly, Senators came with rich experience in foreign policy and other key policy areas. Given there are only hundred senators, most of them get to be chairs/ranking members on key committees. This experience comes in handy in administration. Particularly for presidential candidates without DC experience, a running mate from the senate can go a long way in building relationships with party insiders and assuring the establishment that the future President will have a No. 2 they’ll be able to count on.
Joe Biden was a creature of the senate. He served there for 36 years and was the chairman of the Senate Foreign Relations committee for a long time. So it wouldn’t be surprising if he chooses a senator as his running mate. There are 17 women senators on the Democrat side, the most there have ever been, and each of them is a potential candidate. Some of them like Elizabeth Warren could help unify the two factions of the party while some others like Kamala Harris and Catherine Cortez Masto would make the ticket more racially diverse. Senators such as Tammy Baldwin who come from swing states could help deliver crucial states in the election but their elevation to the vice presidency could put a vital senate seat in play.