Democrats will gain US Senate seats in 2020 and 2022, but lose seats in 2024.

2020- 35 Democratic held US Senate seats are not up for re-election in 2020.
Democrats will hold onto
36)DE(Coons-D)
37)IL(Durbin-D)
38)MA(Markey-D/Kennedy-D)
39)MI(Peters-D)
40)MN(Smith-D)
41)NH(Shaheen-D)
42)NJ(Booker-D)
43)NM(Lujan-D)
44)OR(Merkley-D)
45)RI(Reed-D)
46)VA(Warner-D)
Democrats will pick up
47)AZ special(McSally-R)Kelly-D
48)CO(Gardner-R)Hickenlooper-D
49)NC(Tillis-R)Cunningham-D/Smith-D
50)ME(Collins-R) Gideon-D and Democrats win the 2020 US Presidential Election.
2022- 37 Democratic held US Senate seats are not up for re-election in 2022.
Democrats will hold onto
38)AZ(Kelly-D)
39)CA(Harris-D)
40)CO(Bennet-D)
41)CT(Blumenthal-D)
42)HI(Schatz-D)
43)IL(Duckworth-D)
44)MD(Van Hollen-D)
45)NV(Cortez Masto-D)
46)NH(Hassan-D)
47)NY(Schumer-D)
48)OR(Wyden-D)
49)VT(Leahy-D)
50)WA(Murray-D)
Democrats will pick up
51)NC(OPEN Burr-R)
52)PA(Toomey-R)
53)WI(Johnson-R)
2024-30 Democratic held US Senate seats are not up for re-election in 2024.
Democrats will hold onto
31)AZ(Sinema-D)
32)CA(OPEN Feinstein-D
33)CT(Murphy-D)
34)DE(Carper-D)
35)HI(Hirono-D)
36)ME(King-I/D)
37)MD(Cardin-D)
38)MA(Warren-D)
39)MI(Stabenow-D)
40)MN(Klobuchar-D)
41)NV(Rosen-D)
42)NJ(Menendez-D)
43)NM(Heinrich-D)
44)NY(Gillibrand-D)
45)PA(Casey-D)
46)RI(Whitehouse-D)
47)VT(Sanders-I/D)
48)VA(Kaine-D)
49)WA(Cantwell-D)
50)WI(Baldwin-D)
Democrats win the 2024 US Presidential Election.