Democratic/Republican US Senators up for re-election in 2018 with highest/lowest approval rating.

Democratic US Senators
Sanders-VT 71 Approval 22 Disapproval-Solid Independent/Democratic
King-ME 61 Approval 27 Disapproval-Solid Independent/Democratic
Hirono-HI 60 Approval 24 Disapproval-Solid Democratic
Klobuchar-MN 59 Approval 26 Disapproval-Solid Democratic
Carper-DE 55 Approval 24 Disapproval-Solid Democratic
Heitkamp-ND 55 Approval 32 Disapproval-Lean Democratic
Warren-MA 54 Approval 35 Disapproval-Solid Democratic
Murphy-CT 53 Approval 31 Disapproval-Solid Democratic
Tester-MT 53 Approval 33 Disapproval-Lean Democratic
Manchin-WV 53 Approval 36 Disapproval-Lean Democratic
Cardin-MD 50 Approval 23 Disapproval-Solid Democratic
Nelson-FL 50 Approval 26 Disapproval-Lean Democratic with Scott-R/Likely Democratic without Scott-R
Cantwell-WA 50 Approval 28 Disapproval-Solid Democratic
Gillibrand-NY 49 Approval 24 Disapproval-Solid Democratic
Whitehouse-RI 49 Approval 32 Disapproval-Solid Democratic
Kaine-VA 48 Approval 35 Disapproval-Likely Democratic
Donnelly-IN 47 Approval 26 Disapproval- Lean Democratic
Brown-OH 47 Approval 28 Disapproval- Lean Democratic
Feinstein-CA 47 Approval 33 Disapproval-Solid Democratic
Heinrich-NM 45 Approval 31 Disapproval-Likely Democratic
Stabenow-MI 45 Approval 36 Disapproval-Likely Democratic
Casey-PA 43 Approval 32 Disapproval-Likely Democratic
McCaskill-MO 42 Approval 39 Disapproval-Tossup Democratic
Baldwin-WI 41 Approval 38 Disapproval-Lean Democratic
Menendez-NJ 32 Approval 41 Disapproval-Lean Democratic
Republican US Senators
Barrasso-WY 53 Approval 26 Disapproval-Solid Republican
Cruz-TX 52 Approval 32 Disapproval-Likely Republican
Wicker-MS 49 Approval 26 Disapproval-Solid Republican
Hatch-UT 46 Approval 41 Disapproval-Likely Republican
Fischer-NE 45 Approval 35 Disapproval-Solid Republican
Heller-NV 39 Approval 39 Disapproval-Tossup Democratic