In retrospect, which were realigning elections?

[Skill and Chance]

Really liking the 1800/1856/1896/1952/1992 (1994?) story after seeing 2020 play out.  The realignments look something like this:

1. Agrarian interests become dominant, out-party represents infrastructure interests/early industrialists
2. Early entrepreneurs and industrialists become dominant
3. Urban working class becomes large and powerful enough to demand concessions from #2 while partnering with remnant of #1
4. Suburban middle class becomes dominant, movement to protect and support #3 fades in favor of small government
5. Urban/suburban managerial class becomes dominant, partners with remnant of #3 to seek more government intervention

[Skill and Chance]

One of the most interesting things about the current era is big business and small business sorting into opposite parties.  This is something we haven't really seen since the 19th century.

[Skill and Chance]

The one constant has been non-farm small business owners voting Republican since day 1.   Big business has flipped back and forth other than getting spooked by FDR for about a generation.   

[Skill and Chance]

1896, as it establishes the Republican party into a relatively conservative/lassie-faire party we can trace its roots back to from today.
1932- this elections solidies the Democratic party into being the big government party of the working man for the next 80 years. The strength of FDRs victories can still be seen in the EC today.
1952- the first cracks in FDRs reliable Democratic coalition
1968- the beginning of a major Republican relalignment we will see for several decades; fully comes to an end in 2008.
1980- surprisingly, I don't consider this to be a realignment, I consider Reagan's electoral dominace to come from the electoral strength of Nixon and the critical mass of Republican big tent ideologies front the early twentieth century. This election and 1984, in my opinion is the last great "hoorah" of the Republican party, as moderates and liberals (whom were once Republicans) increasingly become disgusted with strict social conservativism and turn to the Democrats for new answers. This election is basically a continuation of the same ol' same old (1896-1992/2004).
1992- This election is a MAJOR relalignment, one of which I think we are still in but one that is also ending. This election rebrands Democrats as the moderate, centrist party and gives them new found strength in states never before acehivable to them. Obama's electoral success is credited to Clinton's foundation in the EC, not his own. Obama did not create any new coalition we haven't already seen...
2016- cracks in Clinton's electoral coalition.
2024/2028- any sign of the strength the Democrats have shown is quickly eroding as each successful election cycle they win their winning EC margin continues a linear decline. As the Democratic party aligns itself with more of a European left wing party such as the UK Labour, expect it to perform as such... As the religious rights becomes smaller, and the nation more secular, expect the Republican party to slowly put them behind new groups they will try to attract with more liberal stances on abortion and gay marriage.

I'm not really sure the GOP is getting more secular in any meaningful way.  It was reasonable to assume Trump would push the party that way back in 2016, but he didn't really govern that way at all, and the most secular areas of the country swung Dem more than the nation from 2016-20.  I really doubt secular moderates are the future of the GOP.  It's more plausible they break through with religious, relatively socially conservative minority voters who have stuck with the Dems until now. 

Strongly agree with you that the 1980's Republican wins are the tail end of the labor vs. management alignment and Bill Clinton is the dividing line for the modern era.