US Senate sucessor to Bennet-CO, Booker-NJ, Harris-CA, Klobuchar-MN, Sanders-VT, and Warren-MA.

If Bennet(D-CO) becomes POTUS, VP, or CS, Neguse-D.
If Booker(D-NJ) becomes POTUS, VP, or CS, Gottheimer-D
If Harris(D-CA) becomes POTUS, VP, or CS, Linda Sanchez-D
If Klobuchar(D-MN) becomes POTUS, VP, or CS, Otto-D
If Sanders(I/D-VT) becomes POTUS, Douglas-R/Zuckerman-P/D
If Warren(D-MA) becomes POTUS, Swift-R/Healey-D