Democrats need to gain as many US Senate seats in 2020 and 2022 to retain control in 2024.

2020- 35 Democratic held seats are not up for re-election in 2020
Democrats are favored to hold onto
36)RI(Reed-D)
37)MA(Markey-D/Kennedy-D)
38)DE(Coons-D)
39)NJ(Booker-D)
40)OR(Merkley-D)
41)IL(Durbin-D)
42)NM(Lujan-D)
43)VA(Warner-D)
44)NH(Shaheen-D)
45)MN(Smith-D)
Democrats have a 50-50 chance of holding onto
46) MI(Peters-D)
Democrats are favored to pick up
47)CO(Hickenlooper-D)
48)AZ special(Kelly-D)
49)NC(Cunningham-D)
Democrats have a 50-50 chance of picking up
50)ME
51)IA
52)GA special
53)GA regular
2022- 39 Democratic held US Senate seats are not up for re-election in 2022.
Democrats are favored to hold onto
40)HI(Schatz-D)
41)NY(Schumer-D)
42)VT(Leahy-D)
43)CA(Harris-D)
44)CT(Blumenthal-D)
45)MD(Van Hollen-D)
46)IL(Duckworth-D)
47)WA(Murray-D)
48)OR(Wyden-D)
49)CO(Bennet-D)
50)NV(Cortez Masto-D)
51)NH(Hassan-D)
Democrats have a 50-50 chance of holding onto
52)AZ(Kelly-D)
53)GA(Lieberman-D)
Democrats are favored to pick up
54)PA(Toomey-R)
55)NC(OPEN Burr-R)
56)WI(Johnson-R)
57)IA(OPEN Grassley-R)
2024- 34 Democratic held US Senate seats are not up for re-election in 2024.
Democrats are favored to hold onto
35)HI(Hirono-D)
36)VT(Sanders-I/D)
37)NY(Gillibrand-D)
38)MD(Cardin-D)
39)RI(Whitehouse-D)
40)MA(Warren-D)
41)MN(Klobuchar-D)
42)DE(Carper-D)
43)CT(Murphy-D)
44)WA(Cantwell-D)
45)VA(Kaine-D)
46)PA(Casey-D)
47)WI(Baldwin-D)
48)ME(King-I/D)
49)CA(OPEN Feinstein-D)
50)NM(Heinrich-D)
51)NJ(Menendez-D)