Alaska is following the same trends as Colorado was in the 1990s, as there's a lot of in-migration from relatively liberal types and the state is small enough that when they get mobilized politically that change could be pretty drastic. It's also a state that has a
very suburban GOP and may be susceptible to a broader nationwide trend towards the Democrats in suburbs. It's also very elastic and used to voting for both parties at the local level.
Utah, like Alaska, is broadly a very suburban state, where the suburbs can consistently outvote rural areas. Utahn suburbs, since they are very Mormon, are
much more right-wing than other areas; the simple question is where the McMullin dissidents will go next. Utah has enough of a white-liberal Democratic base in SLC that if they decide to vote Democratic presidentially, the state
will flip, indeed to a high-single-digits Democratic victory. I suspect this is a plausible scenario for 2020 in the event of Trump being broadly unpopular, but unless Trumpism is
very successful at taking root in the Republican Party I doubt Utah will continue to vote Democratic into the 2020s. Still, the state is
very young and the people have
very cosmopolitan values (see Utah being the only Republican-governed state whose Governor announced that Syrian refugees were welcome); it is an option for the immediate future.
The other states seem less likely. A Mormon third-party that captured
all Mormons would put Idaho into play, but it's clear that rural Mormons weren't that offended by Trump and Idaho Mormons are much more rural than their Utah counterparts. Montana Democrats are dependent on white working-class votes and it doesn't seem like a very logical place for modern Democratic Party gains.
I suspect Wyoming is vulnerable to an influx of liberals like what happened to VT and CO, and is happening to AK; the parallel seems to be areas where tourism is a very big part of the economy, and WY has that going for them; they're also small enough that it wouldn't necessarily take a very large influx to radically change the state's political culture. But...it clearly isn't happening yet. And it would take 15-20 years to play out.
Well...yeah. Every losing party has a few bright spots. Gerlach, Shays, and Heather Wilson all survived 2006. Boren, Ross, and Giffords all survived 2010. But if 2018 is a big-ish wave (not implausible if Trump's approvals are perpetually sh**tty), I'd wager that 3/4ths of the Clinton Republican congresspeople will lose. People like IRL, Curbelo, Comstock, Coffman, Valadao, and Paulsen, all seeming to be electoral superstars, would be fighting for their political lives. Then there'll be all those people who sit in marginal Trump seats (like you mentioned) that would be toppled in such a scenario. Dems only need 24 seats total, though they should shoot for more like 35-40 to allow for ideological flexibility to account for the Collin Petersons and Kurt Schraders of the caucus.
People are severely underestimating the odds of a Speaker Pelosi redux (if Democrats can compete in formerly-safe seats that swung heavily D in 2016, and I suspect that if Trump's approvals stay where they are then they'll be able to, then the Republican gerrymanders are broken and the path to the Speakership is very straightforward) and severely overestimating the odds of SML Schumer anytime within the next six years (maybe if 2018 and 2020 are ludicrously D-favorable years, it can happen, but I suspect Democrats will need to wait until 2022 for another shot at Senate control).
My very crude universal swing model for 2018 (Rs win every seat that voted for Trump by a margin of 5 points or more; Dems win everything else) showed D+30 in the House and R+4 in the Senate. I doubt Democrats will actually gain D+30 in the House, since House races are less nationalized than senatorial ones and there's a lot of popular Republican incumbents in downballot Republican territory that Democrats would need to take out, but the point is that large Democratic gains in 2018 are a quite plausible scenario.
