Incoming US Senators if Democrats regain control of the US Senate in 2020.

Democratic Hold.
MA(Kennedy-D)if he defeats Markey-D in the primary.
NM(Lujan-D) succeeds retiring Democratic US Senator Tom Udall(D-NM)
Republican Hold
KS(Kobach-R) succeeds retiring Republican US Senator Pat Roberts(R-KS)
OK(Pruitt-R) if Inhofe-R retires.
TN(Hagerty-R) succeeds retiring Republican US Senator Lamar Alexander(R-TN)
WY(Lummis-R) succeeds retiring Republican US Senator Mike Enzi(R-WY)
Democratic turned Republican
AL(Sessions-R) defeats Jones-D. 46D
VT(Douglas-R or Dubie-R) gets appointed by current Republican Governor Phil Scott to Bernie Sanders VT US Senate seat. Whoever gets appointed will have to run in the 2021 Special Election. The winner of the Special Election is likely to be a Democrat.- Peter Welch- or Peter Shumlin-.
Republican turned Democratic- need 6
AZ special(Kelly-D) defeats McSally-R. 46/47D
CO(Hickenlooper-D) defeats Gardner-R. 47/48D
GA regular(Tomlinson-D) defeats Perdue-R. 48/49
GA special(Warnock-D) defeats Loeffler-R or Collins-R. 49/50
ME(Gideon-D) defeats Collins-R. 50/51
NC(Cunningham-D) defeats Tillis-R. 51/52