Flake (R-AZ) if the Democratic nominee is Mark Kelly or Greg Stanton?
Nelson (D-FL) if the Republican nominee is Rick Scott or Pam Bondi?
Donnelly (D-IN) if the Republican nominee is Luke Messer or Todd Rokita?
McCaskill (D-MO) if the Republican nominee is Josh Hawley or Eric Schmitt?
Tester (D-MT) if the Republican nominee is Matt Rosendale or Corey Stapleton?
Heller (R-NV) vs Rosen (D-NV)?
Heitkamp (D-ND) vs Cramer (R-ND)?
Brown (D-OH) vs Mandel (R-OH)?

Pat Leahy (D-VT) will complete 48 years when his term expires in 2022. Leahy will be 82 if or when he decides to run for re-election in 2022, 88 if or when he decides to run for re-election in 2028. Leahy will be in the US Senate for at least 54 years.

Does McCaskill's chances of winning re-election improve?

1)US Senate against Flake-R or Ward-R
2)Governor against Ducey-R.
Stanton should run for Governor if Mark Kelly decides to run for the US Senate but if Mark Kelly decides not to run, Stanton should run for the US Senate. Sinema-D is running for re-election to the US House, Kirkpatrick-D is running for the US House against McSally.

Reid,Cortez Masto, and Kihuen. Rosen is going to be the Democratic nominee for the 2018 NV US Senate Race. Titus should run for re-election to the US House-NV-1CD, Miller or Marshall should run for Governor or the US House-NV-3CD.

these scenarios?
2018-Hatch (R-UT) vs Jim Matheson-D
2020-Cochran (R-MS) vs Jim Hood-D
2022-Leahy (D-VT) vs Phil Scott-R

Former US Senator Moss (D-UT)(What do you call a US Senator who served for 18 years? You call him home) against Hatch in 2018 (What do you call a US Senator who served for 42 years? You call him?

Trump is Bush43
Pence is Quayle (Indiana)

AZ(Kelly-D)Democratic Favored 24D
CA (Feinstein-D)Democratic Favored 25D
CT (Murphy-D)Democratic Favored 26D
DE (Carper-D)Democratic Favored 27D (if Carper-D retires-Blunt Rochester-D)
FL (Nelson-D)Democratic Favored 28D
HI (Hirono-D)Democratic Favored 29D
IN(Donnelly-D)Democratic Favored 30D
ME (King-I/D)Democratic Favored 31D
MD (Cardin-D)Democratic Favored 32D (if Cardin-D retires-Sarbanes-D)
MA (Warren-D)Democratic Favored 33D
MI(Stabenow-D)Democratic Favored 34D
MN (Klobuchar-D)Democratic Favored 35D
MS (Bohren-D)Republican Favored 45R
MO (McCaskill-D)Democratic Favored 36D
MT (Tester-D)Democratic Favored 37D
NE (???-D)Republican Favored 46R
NV (Rosen-D)Democratic Favored 38D
NJ (Pallone-D)Democratic Favored 39D
NM (Heinrich-D)Democratic Favored 40D
NY (Gillibrand-D)Democratic Favored 41D
ND (Heitkamp-D)Democratic Favored 42D
OH (Brown-D)Democratic Favored 43D
PA (Casey-D)Democratic Favored 44D
RI (Whitehouse-D)Democratic Favored 45D
TN (Berke-D)Republican Favored 47R
TX (O'Rourke-D)Tossup(former Trump spokesperson Pierson-R could challenge Cruz-R in primary or run as an Independent)
UT (Wilson-D)Tossup (Hatch-R is highly unpopular,McMullin-I/R runs as an Independent)
VT (Sanders-I/D)Democratic Favored 46D
VA (Kaine-D)Democratic Favored 47D
WA (Cantwell-D)Democratic Favored 48D
WV (Manchin-D)Democratic Favored 49D
WI (Baldwin-D)Democratic Favored 50D
WY (???-D)Republican Favored 48R
All of the Trump State Democratic incumbents US Senators up for re-election in 2018 win re-election due to the Anti Trump Republican wave and lack of top tier Republican challengers.