2017
NJ(Murphy-D)Democratic Favored 1D
VA (Northam-D)Democratic Favored 2D
2018
AL (Cobb-D)Republican Favored 1R
AK (Walker-I/D)Independent Favored 1I
AZ (Garcia-D)Tossup
AR (Eldridge-D)Republican Favored 2R
CA (Newsom-D)Democratic Favored 3D
CO (Kennedy-D)Democratic Favored 4D
CT (Lembo-D)Democratic Favored 5D
FL (Graham-D)Democratic Favored 6D
GA (Abrams-D)Tossup
HI (Ige-D)Democratic Favored 7D
ID (Balukoff-D)Republican Favored 3R
IL (Pritzker-D)Democratic Favored 8D
IA (Boulton-D)Republican Favored 4R
KS (Brewer-D)Republican Favored 5R
ME (Dunlap-D)Democratic Favored 9D
MD (Baker-D)Republican Favored 6R (will get elected in 2022 when open seat)
MA (Warren-D)Republican Favored 7R (will get elected in 2022 when open seat)
MI (Whitmer-D)Democratic Favored 10D
MN (Walz-D)Democratic Favored 11D
NE (???-D)Republican Favored 8R
NV (Miller-D)Democratic Favored 12D
NH (Marchand-D)Tossup (will get elected in 2020 when open seat-Sununu-R makes a US Senate run)
NM (Lujan Grisham-D)Democratic Favored 13D
NY (Cuomo-D)Democratic Favored 14D
OH (Sutton-D)Democratic Favored 15D
OK (Edmonson-D)Tossup
OR (Brown-D)Democratic Favored 16D
PA (Wolf-D)Democratic Favored 17D
RI (Raimondo-D) Democratic Favored 18D
SC (Hutto-D)Republican Favored 9R
SD (Sutton-D)Republican Favored 10R
TN (Dean-D)Republican Favored
TX (???-D)Republican Favored 11R
VT (Minter-D)Republican Favored 12R
WI (Vinehout-D)Republican Favored 13R
WY (Rothfuss-D)Republican Favored 14R
2019
KY (Lundergan Grimes-D)Republican Favored 15R
LA (Bel Edwards-D)Democratic Favored 19D
MS (Hood-D)Tossup
2020
DE (Carney-D)Democratic Favored 20D
IN (????-D)Republican Favored 19R
MO (Kander-D)Republican Favored 20R
MT (Cooney-D)Democratic Favored 21D
NH (Marchand-D)Democratic Favored 22D
NC (Cooper-D)Democratic Favored 23D
ND (???-D)Republican Favored 21R
UT (McAdams-D)Republican Favored 22R
WA (Inslee-D)Democratic Favored 24D
WV(Justice-D)Democratic Favored 25D

In 2006 US Senate Election cycle, Bush43-R State Democratic incumbents in FL (Nelson-D),NE (Nelson-D),NM (Bingaman-D/Bush lost it in 2000 but won it in 2004),ND (Conrad-D),and WV (Byrd-D) won re-election and Democrats picked up 6 additional seats, 2 from Kerry States (PA and RI)4 from Bush States (MO,MT,OH,and VA)-Democrats ended up with 51 seats.
In 2008 US Senate Election cycle, McCain-R State Democratic incumbents in AR (Pryor-D),LA (Landrieu-D),MT (Baucus-D),SD (Johnson-D),and WV (Rockefeller-D) won re-election and Democrats picked up 8 additional states, 7 from Obama states (CO,MN,NH,NM,NC,OR,and VA) and 1 from McCain state (AK)-Democrats ended up with 59 seats.
2018-There are 10 Trump State Democratic incumbents up for re-election -FL (Nelson-D),IN (Donnelly-D),MI (Stabenow-D),MO (McCaskill-D),MT (Tester-D),ND(Heitkamp-D),OH (Brown-D),PA (Casey-D)WV (Manchin-D),and WI (Baldwin-D)
Due to Trump and McConnell's unpopularity, Democrats will hold onto most or all of those seats.
Nelson (FL) wins re-election against Scott or any other top tier Republican challenger.
Donnelly (IN)victory is determined by who the Republican nominee is going to be
Stabenow (MI) wins re-election
McCaskill (MO)victory is determined by who the Republican nominee is going to be
Tester (MT)wins re-election but margin of victory won't be like Baucus's
Heitkamp (ND)wins re-election but margin of victory won't be like Conrad or Dorgan's
Brown (OH)wins re-election
Casey (PA)wins re-election
Manchin (WV)wins re-election but margin of victory won't be like Byrd or Rockeller's.
Baldwin (WI)win re-election but margin of victory will be like Feingold's 2004 victory.
Democrats could pick up 2 to 4 additional seats. AZ,NV,TX (see VA 2006)and UT (if Matheson-D runs) Democrats could end up with 52 seats.
2020-Democrats could get to 60 seats by picking up AK,CO,GA,IA,MT (if Bullock-D runs),NC,and TX (if Castro-D runs).and Collins (R-ME) becomes an Independent caucusing with Democrats.

Least Vulnerable
MI (Stabenow-D)
PA (Casey-D)
Somewhat Vulnerable
WV (Manchin-D)
FL (Nelson-D)
WI (Baldwin-D)
Vulnerable
ND (Heitkamp-D)
MT (Tester-D)
OH (Brown-D)
Most Vulnerable
IN (Donnelly-D)
MO (McCaskill-D)

Democrats lose IN and MO but pick up NV,AZ (if Flake-R loses in the Republican primary),UT (if Matheson-D runs) and TX (if O'Rourke-D runs a strong campaign)

Democrats will regain control of the US Senate in 2020 by picking up
AK(if Bill Walker-I/D runs)
CO
GA-the outcome of 2018 GA Governors Race could determine whether Democrats can win a GA US Senate Race.
IA (if Vilsack-D runs)
ME (if Collins-R retires or loses in the primary)
MT (if Bullock-D runs)
NC
TX (if Cornyn-R retires and Castro-D runs)

Begich(D-AK) won the 2008 AK US Senate Race against a longtime Republican incumbent Ted Stevens (who back then was a convicted felon)
Hatch (R-UT) is the Ted Stevens of UT without the felony conviction.
Democrats could nominate Jim Matheson or Ben McAdams (Mayor of Salt Lake County),Merrill Cook (R-UT) could run as an Independent along with Evan McMullin.

Announced Top Tier Democratic candidates
Rosen (D-NV)
O'Rourke (D-TX)
Democrats will win NV,TX is an uphill battle.
Announced Top Tier Republican candidates
Mandel (R-OH)
Jenkins (R-WV)
Democrats will hold onto OH and WV.
Potential Top Tier Democratic candidates
Stanton (D-AZ)
Berke (D-TN)
McAdams (D-UT)
Democrats will pick up AZ,TN is a long shot and UT is an uphill battle.
Potential Top Tier Republican candidates
Scott (R-FL)loses
Messer(R-IN)could win
Amash(R-MI)loses
Paulsen(R-MN)loses
Hawley (R-MO)could win
Stapleton (R-MT)could win
Kean (R-NJ)loses
Sanchez (R-NM)loses
Cramer (R-ND)could win
Barletta (R-PA)loses
Comstock (R-VA)loses
Fitzgerald (R-WI)loses.

CO
Gardner-R polls at 39 percent
Democratic challenger polls at 53 percent.
Democratic nominee could either be Hickenlooper or one of the losing 2018 Democratic candidates for Governor.
IA
Ernst-R polls at 48 percent
Democratic challenger polls at 41 percent.
If Democratic nominee is Vilsack(Tom or Christie)-The race becomes a tossup.
NC
Tillis-R polls at 44 percent
Democratic challenger polls at 48 percent
If the Democratic nominee is Josh Stein, Tillis-R loses.
2020 will be a correction for any seat Democrats lose in 2018.
In 2018- Democrats will pick up AZ-(Flake-R is likely to lose in the Republican primary) and NV (Heller-R has a top tier Democratic challenger and represents an anti Trump State) 50R 48D 2I/D
Democrats could also lose US Senate seats in strong Trump states IN,MO,MT,ND,and WV. 55R 43D 2I/D
2020-No Democratic held US Senate seat is likely to go Republican. MI (Peters-D),MN (Franken-D),NH(Shaheen-D),and VA (Warner-D) will win re-election.
Democrats will pick up
CO -Hickenlooper-D,Johnston-D,Kennedy-D,Perlmutter-D or Polis-D 54R 44D 2I/D
GA-Abrams-D,Evans-D,or Ossoff-D 53R 45D 2I/D
IA-Culver-D or Vilsack-D 52R 46D 2I/D
ME-Michaud-D or Pingree-D (Collins-R gets a primary challenge from LePage-R) 51R 47D 2I/D
NC-Ross-D or Stein-D 50R 48D 2I/D
If Trump-R loses re-election, Democrats regain control of the US Senate in 2020.
Democrats could pick up AK in 2020 if Independent Governor Bill Walker runs and caucuses with the Democrats or Ethan Berkowitz-D.

Democrats had a majority in the US Senate.
There would have been 5 Liberal Judges in the Supreme Court.
Ginsburg,Breyer,Sotomayor,Kagan,and Garland.

Landslide Margin Republican Victory
WY-Barrasso-R 45R
NE-Fischer-R 46R
MS-Wicker-R 47R
Low Double Digit Margin Republican Victory
TN-Corker-R 48R
UT-Hatch-R 49R
High Single Digit Margin Republican Victory
TX-Cruz-R 50R
Narrow Margin Republican Victory
AZ-Flake-R 51R
Narrow Margin Democratic Victory
MO-McCaskill-D 24D
IN-Donnelly-D 25D
NV-Heller-R/Rosen-D 26D
ND-Heitkamp-D 27D
MT-Tester-D 28D
High Single Digit Margin Democratic Victory
OH-Brown-D 29D
FL-Nelson-D 30D
WI-Baldwin-D 31D
Low Double Digit Margin Democratic Victory
WV-Manchin-D 32D
NM-Heinrich-D 33D
PA-Casey-D 34D
VA-Kaine-D 35D
MI-Stabenow-D 36D
Landslide Margin Democratic Victory
ME-King-I/D 37D
NJ-Menendez-D or Democratic Primary Winner-D 38D
MA-Warren-D 39D
WA-Cantwell-D 40D
CT-Murphy-D 41D
MN-Klobuchar-D 42D
MD-Cardin-D 43D
CA-Feinstein-D 44D
RI-Whitehouse-D 45D
DE-Carper-D 46D
NY-Gillibrand-D 47D
HI-Hirono-D 48D
VT-Sanders-I/D 49D

NM-Heinrich-D in a race against Susana Martinez-R,John Sanchez-R,or Heather Wilson-R?
VA-Kaine-D in a race against Tom Davis-R or Barbara Comstock-R?
Both of these Democratic incumbents are likely to win by a high single to low double digit margin.