Could the Massachusetts State Senate or Wyoming State Senate become all D/all R soon?

[mpbond]

The MA GOP currently holds three seats. Two of them could go to the Dems in the near term. The First Essex & Middlesex district contains the city of Gloucester and many northern outer Boston Suburbs. It likely voted for Biden by over 20 points. It is held by Bruce Tarr who is locally popular and if he retires, it would be a nearly guaranteed D Flip. The Plymouth and Norfolk District contains several very wealthy Boston suburbs on the South Shore, which is a historically Republican region due to its wealth. Biden likely won it by double digits as well. If the suburban realignment trickles down ballot, as it has in the rest of the Boston suburbs, this seat will flip. The third seat is The Worcester & Norfolk district, located in the conservative Blackstone valley. This region is one of the truly conservative regions in Massachusetts, however as the Worcester and Boston suburbs grow into this area, it is shifting towards the Democrats as well. Biden narrowly won this seat as well. However down ballot Dems likely wont be competitive here for a couple of cycles. So, if current suburban trends continue, Bruce Tarr retires, and Dems hold all their competitive seats (theres a few), they could hold all the seats at some point. Barring some aggressive D Gerrymander, I would say this could happen by the end of the decade, but everything would have to go perfectly for the Dems.

[mpbond]

The third seat is The Worcester & Norfolk district, located in the conservative Blackstone valley. This region is one of the truly conservative regions in Massachusetts, however as the Worcester and Boston suburbs grow into this area, it is shifting towards the Democrats as well.

Clinton and Markey (in 2014) both lost this district by less than 2 points, so it's probably not "truly conservative" in the national sense but only by the standards of Massachusetts  

Your'e absolutely right, by Massachusetts standards it's conservative, but not so much by national standards. As with anything New England this means it's also like Charlie Baker/Mitt Romney conservative rather than Trump Conservative. The Blackstone valley has always been conservative compared to the rest of the states, however the Worcester suburbs are outweighing it more and more as time goes on. I forgot about this in my original post but this isn't even the most Republican seat, theres a neighboring district in the western Worcester County that voted for Trump by 10pts in '16 but it's held by a Dem (although I think Biden may have narrowly flipped it last year). Goes to show that the right Dem could definitely win any of these districts.

[mpbond]

Wyoming is unlikely because I think the two seats represented by Ds are significant Native areas. 

There’s also the point that both Wyoming, a very urban mountain state, and Massachusetts, a pretty catholic white ethnic state, are trending towards being more competitive, not less. 

Zaybay has already shown that, if anything, the opposite is true for Massachusetts’ trend, but this is also a very odd way to frame its political demographics. The reason that it is so D, and not going to change anytime soon, is that it is the most college-educated state in the nation, and a fairly secular one (IIRC, Boston shockingly actually has one of the lowest % of practising Catholics of any of the historically white ethnic major cities).

I still stand by my claim that the states are trending in rather opposite directions.  Top-line trends towards Democrats in Massachusetts are mostly the result of D swings in populous Boston and its suburbs, but parts of Western Mass and Bristol Co trended toward Trump in both 2016 and 2020.  In the current alignment, I think Massachusetts will abandon being so idiosyncratically Democratic and fall into the usual, national trend of urban/suburban - exurban/rural political divergence.  That doesn't mean I think MA will be remotely competitive anytime soon, but I think later this decade and into the 2030s it won't be unusual for non-metro parts of the state to prefer sending Republicans to the state house.     

All of this pretty much applies in the opposite partisn direction in Wyoming. 

The only parts of Western Mass that swung towards Trump in 2020 are Hispanic urban cores and a few random towns in Berkshire County. There are some more places that trended towards Trump, but not by much and they were mostly low-population rural areas. Rural Massachusetts (a) is a very small percentage of the state's population, and (b) has way too many people who aren't "culturally rural" enough to vote Republican.

The people who live in the Pioneer Valley of western Mass would fit in better in San Francisco than they would in any other non-New England rural area. There are several factors to this, including an economy based on higher education, art, and tourism, but even the areas not near universities or tourism are still rock-solid democratic due to the areas high rates of people with college educations and the overall secularism of the region. As you said, it's just a completely different culture to other rural areas.