It's less than six months from election day, so why not handicap the current state of the 2020 Senate races?
I'm going to list the (competitive) races in order of likelihood to flip to the opposing party.
1. Alabama (Doug Jones - D): You know that West Wing plot where the Democratic nominee in a super-Republican district dies before election day, and Sam Seaborn offers to run in the special election if the dead guy somehow ends up winning? And then every confluence of luck and God and good fortune smiled and the dead guy did win, forcing Sam into a congressional run doomed as soon as it began?
That's kind of Doug Jones' re-election campaign. Everything -- everything -- had to break in increasingly ludicrous fashion for a Democrat to win a Senate seat in Alabama, right down to his opponent being an actual pedophile. And it still was a 2 point race. This was a great victory, and Jones deserves to be showered with plaudits and praise for it. But it'd take another miracle for him to win in 2020, and I don't see it. The only bright spot is that former Auburn football coach Tommy Tuberville looks likely to best ex-Senator and former Trump AG Jeff Sessions to become the GOP nominee -- not because Tuberville is better, but because one of the few joys of the Trump era has been watching him repeatedly wreck the careers of his erstwhile friends.
2. Colorado (Cory Gardner - R): Colorado, like Nevada, is a state that seemed to go from red to light blue, skipping entirely over purple in the process. Cory Gardner never got the memo, and has legislated like a GOP diehard for his entire first term -- never even gesturing at a pivot toward the center. The reward for his Trumpist loyalty is to be polling down double digits against Colorado Governor John Hickenlooper (doing the right thing running for Senate instead of a quixotic Presidential campaign). It's hard to see how he survives -- he ranks below Jones only because Colorado isn't so solidly blue that a Republican victory would require divine intervention.
3. Arizona (Martha McSally - R [special]): Every once in awhile, one comes across a politician who seems perfectly fine on paper, who doesn't seem to have any particular attributes that make her especially lovable or loathable, yet who voters for whatever reason just don't cotton to. Martha McSally seems to be one of those pols. She just lost a Senate race in 2018 to Kyrsten Sinema in a mild upset that presaged Arizona suddenly becoming a real Democratic target, then immediately got appointed to fill the shoes of departing Republican Senator Jon Kyl. Now she's polling down again to Mark Kelly (astronaut husband of shooting survivor and ex-Rep. Gabby Giffords), in a state where Biden is posting some very impressive numbers. Other politicians might be able to reverse the tide. But McSally just doesn't seem to vibe with the folks she needs to, and the trend lines aren't pulling her way. The most recent poll to drop in Arizona has her losing by a crushing 13 point margin.
4. Maine (Susan Collins - R): This would be among the sweetest fruits for me, and Sara Gideon has a very strong shot to take out Moderate Republican(tm) Susan Collins. Maine remains blue at the presidential level, and Collins once sky-high approvals have been in free fall as she's played loyal foot soldier to McConnell and Trump. Yet it's hard not to imagine she's stockpiled some good will from her (however tattered) reputation as a moderate, and Maine more so than anywhere in New England has some areas that are surprisingly Trump-friendly. This will be a real slugfest.
5. North Carolina (Thom Tillis - R): The "new south" -- educated, suburban, professional, racially diverse, and increasingly blue-friendly -- is creeping up and down the Atlantic coast. Virginia's already been taken over. Georgia an increasingly plum target. But the next domino most likely to fall is North Carolina -- still the palest shade of red leaning, but a place where Democratic fortunes appear to be waxing. Tillis has two other things cutting against him: he'll be sharing a ballot with wildly popular Democratic Governor Roy Cooper (who appears to be thrashing any GOP challengers), and a flood of bad press hitting his Senate colleague Richard Burr for allegedly dumping stock before the coronavirus news really broke. Democratic nominee Cal Cunningham is polling well here -- either moderately ahead or at worst tied.
6. Montana (Steve Daines - R): Governor Steve Bullock is another entry in the "thank you for abandoning a ridiculous POTUS bid and running for Senate instead" list, and he instantly turns this race into a real Democratic opportunity. Montana has been quietly getting more competitive over the past few years as the western half of the state and what passes for "cities" turn bluer, and Democratic Senator Jon Tester won a hotly contested 2018 Senate race by a close but not squeaky-thin 3.5% margin. Daines has the advantage of incumbency plus Trump's coattails, but Bullock is popular statewide. This has flown under the radar a bit, and I think Bullock's got a real shot.
7. Georgia (Kelly Loeffler - R [special]): This would place a lot higher if I was ordering based on "likelihood the incumbent loses". Loeffler, only recently appointed by Governor Brian Kemp, is abysmally unpopular in the Peach State, and right now she's polling fourth in a free-for-all election (behind fellow Republican Doug Collins and then two Democrats). The reasons are myriad -- Trump made it clear she was not his choice for the appointment, and she too has gotten into hot water over coronavirus-related trading -- but the end result is she's unlikely to even advance to the run-off. Unfortunately for Democrats, run-offs in Georgia have tended to sharply favor the GOP, so the most likely person to emerge from the scrum is Collins -- an even further-right Trump loyalist. There's also the alarming possibility that, in a highly fractured field, Loeffler manages to squeak into second and lock Democrats out entirely. Of course if that happens, Loeffler's only hope to prevail is to attract cross-over votes ....
8. Michigan (Gary Peters - D): Outside Alabama, this is by far the GOP's best chance for a 2020 Senate pickup. John James is a very strong candidate who ran a surprisingly close race against Debbie Stabenow in 2018, and he's back for a second crack at the Senate. Peters is not as well established as Stabenow was, and 2020 will likely not be as big a blue wave year as 2018 was. On the other hand, Democratic fortunes in Michigan seem to be on the rise, and Biden should perform better there than Clinton did in 2016. That's enough to make Peters the favorite, but not an overwhelming one.
9. Iowa (Joni Ernst - R): Once the ultimate bellwether, Iowa has seemingly been largely written off as a legitimate Democratic target, and for a long time Joni Ernst seemed to be coasting to re-election. But her numbers are surprisingly soft -- two polls this month have her deadlocked with her two most likely Democratic challengers -- and Democrats did win three of four Iowa House seats in 2018. She's definitely still the favorite, but an upset can't be written off.
10. Georgia (David Perdue - R): The other Georgia race, minus the particular "complexities" raised by Loeffler's unique unpopularity. That means most of the above analysis applies, but only more so for the Republicans. Georgia continues to creep towards purple status, but odds are it won't quite get there in 2020.
11. Kansas (Open [Pat Roberts] - R): Kris Kobach blew the Governor's race for the GOP in 2018, but that hasn't deterred him from seeking the Senate nod in 2020. It's possible he'll get it, and so it's possible he'll lose again. Democrats have rarely been competitive in the Sunflower State, but 2018 showed they had a heartbeat. Meanwhile, the state Republican Party has been in a state of near-civil war for years between (relative) moderates and true firebreathers. The latter camp had their man in the Governor's mansion in the form of Sam Brownback, and his experiment in scorched-earth conservative governance led the GOP to unprecedented unpopularity in a state they normally dominate in.
12. Kentucky (Mitch McConnell - R): I know I said Susan Collins would be the sweetest fruit, but if Mitch McConnell goes down I'll revise that assessment. It's unlikely -- Kentucky is blood red at the Presidential level, and McConnell has effectively infinite resources at his disposal. But Andy Beshear's win of the Governor's mansion showed that Democrats still can win statewide if the stars align, and McConnell, for all his power and sway, is actually very unpopular in his home state. A definite long shot, but not wholly out of range.