Who succeeds Harris(D-CA),Bennet(D-CO),Klobuchar(D-MN),or Gillibrand(D-NY)?

US Senators Harris(D-CA), Bennet(D-CO), Klobuchar(D-MN), and Gillibrand(D-NY) are seeking the 2020 Democratic Nomination for President? Neither of them are up for re-election in 2020. All of them come from States with Democratic Governors.
CA- Garcetti-D, Padilla-D,Swawell-D, or Yee-D
CO- Crow-D, DeGette-D, Neguse-D or Perlmutter-D
MN- Craig-D, Flanagan-D, McCollum-D, or Phillips-D
NY- Hochul-D, Maloney-D, Rice-D, or Suozzi-D