My thoughts, feel free to criticize. I'll include thoughts on leg races too
AL: Safe R. It'll be interesting here if Strange goes for Senate rather than Gov as expected - could be a free for all on GOP side. Not that it matters. Leg obviously Safe R
AK: Lean I. I think Walker pulls it out with his quirky coalition he's built here. Goofiness ensues in legislature, very unpredictable
AR: Hutch seems popular, no issue there. Leg is beyond Safe R
AZ: Could get interesting in Mauricio's. Is the AZ Senate close enough for D gains? I think yes, though short of a flip. Ducey could be vulnerable to a Stanton run. There are some row offices young Democrats could line up to challenge, too, though many GOP row officers seem pretty moderate.
CA: Likely D, if only because of Top Two. Leg should stay supermajority, perhaps even grow.
CO: Lean D. I think Ds should be favored to take back trifecta and I'll predict them to win 1 row office
CT: Tossup if Malloy runs, Lean D if he's smart and doesn't. Maybe Himes jumps in? Dems should win a seat or two to regain breathing room in Senate
FL: Tossup/Tilt R: Only because the D bench is crap. I think Gwen Graham makes a solid recruit though and Dems could narrow GOP majorities in the legislature. Maybe 1 row office gets picked off too
GA: Lean R due to runoff. The GOP primary will be nuts. Leg could narrow, maybe Dems get 1 row office with a good recruit and flop on GOP side. Does Carter run again?
HI: utterly Safe D. Can't Rs win back a Senate seat?
ID: Safe R, obviously
IL: Lean D. Best pickup opportunity IMO. Maybe Dems can expand leg margins again too
IA: Tilt R. I expect Reynolds to be the next Governor here. Dems scrape back some seats in leg, probably not enough to flip either
KS: Tilt R. Will be interesting with Brownback so radioactive. Svaty could be a strong contender
ME: who the f knows. I doubt Collins runs. Poliquin would be a strong GOP recruit. I'll say Dems flip the legislature
MD: Tossup/Tilt D: I know Hogan is popular but I see Delaney running and winning, albeit narrowly. Dems grow leg margins
MA: Tossup/Tilt R: Mass loves it some moderate R guvnahs, and Setti Warren seems a lower tier recruit
MI: Tilt D. I think Whitmer wins narrowly. Dems retake House and narrow margins in Senate, maybe flip a row office or two
MN: Lean D. Swanson runs strong in outer state and Dems sweep row offices again. Flip at least one chamber if not both.
NE: Likely R. I know Rockets is basically Brownback north but who runs? Do Dems focus on Senate first
NH: Too early to say. This place swings like crazy.
NM: Likely D. Udall or Balderas would dominate.
NV: Likely D. Don't think GOP has anyone like Sandoval left. Calculus changes if Heller runs, though I doubt he does
NY: Likely D. Hopefully Bharara primaries Cuomo. This could be the year Democrats flip the Senate.
OH: Tossup/Tilt R. I think it'll be narrow, but Republicans win. Leg margins tighten narrowly
OK: Likely R. It'd be interesting if Boren runs, which I doubt
PA: Likely D. Think Wolf runs again and wins. Dems narrow disadvantage in legislature.
Ri: Likelu D. Raimondo wins again, though there could be a primary.
SC: Safe R without an open seat.
SD: Likely R. I think Jackley wins primary.
WI: Tossup. Does the Walker/WOW machine carry the day? Is Walker running again? He'll be the top target for Democrats. Leg depends on what happens with this lawsuit that just went down. Could see a big year here for Team D.
WY: Hahahhaa
This list seems good to me, with the exception of a few:
Maryland (Leans R): I'm not convinced Democrats can knock off an incumbent Gov who is this popular. Perhaps if they can find a way to make him more unpopular? If there is a ginormous wave, perhaps he gets swept away anyway.
Nevada (Tossup): Honestly it's hard for me to give Democrats anything better than a toss-up on this. They have had an amazing inability to win a gubernatorial race here in literally almost a generation now. I'm not saying they definitely can't because they haven't in so long, but that I'm less inclined to believe it's an automatic win, even in a wave.
I'm not too bullish on IA or OH either, but no other comments on them. Overall I do not think 2018 will be kind to Republicans for numerous reasons, so to me it's just a matter of how bad.