1. Thread on Re-aligning Elections: V.O. Key Jr. defined a "Critical Election" as "a type of election in which there occurs a sharp & durable electoral realignment between parties." 1932 is often used as an example, as it started a string of 5 Democratic Presidential victories:

2. However, if we look at where FDR gained more than his nationwide gain (counties in blue) vs where he gained less (counties in red), we see that many of FDR's biggest gains were in areas like the Great Plains that didn't stay with Democrats through the rest of the New Deal era:

3. So 1932 was a Re-aligning Election in the sense that it was a huge national swing towards the Democrats & was the start of an era of Democratic dominance. But it wasn't necessarily a Re-aligning Election in terms of voter blocs shifting decisively into their future coalitions.

4. Instead, the origin of the New Deal Coalition may have begun 4 years earlier, in 1928. Under Catholic nominee Al Smith Democrats made big gains in the cities, among northern industrial workers, & with ethnic/racial minorities, all key parts of the Democrats' future coalition:

5. On the other hand, Smith's massive losses in the South didn't stick, as in 1932 FDR was able to re-gain the Southern Protestant voters who had abandoned the Dems in 1928. So 1928's changes were only a decisive/lasting re-alignment in the North, but were temporary in the South.

6. Another possible Re-aligning Election was not 1928 or 1932, but instead 1936. Many of the most iconic New Deal Coalition areas began voting heavily for FDR that year, including industrial areas of E OH/MI, the Upper Peninsula of MI, the MN Iron Range, & the coal mines of SW WV

7. Obviously it can be hard to choose which years count as Re-aligning Elections, as most major shifts take several elections to play out. It's much easier to pick out elections that were NOT re-alignments. A good example is 1944, where the parties' coalitions were mostly stable:

8. What about more recent Re-aligning Elections? The "Reagan Revolution" of 1980 is often cited as an example. 1980 started a streak of 3 straight GOP Presidential victories, & many voters Reagan flipped in the South, Great Plains, & Rocky Mountains stayed with the GOP long term:

9. However, if we measure how much counties shifted their position relative to the nation in each election (the "Average Absolute Trend"), it's not 1980 that jumps out, but instead 1964 & 1976 that saw large county-level re-alignments in voting patterns (1928 also stands out):

10. 1964 saw huge swings towards the GOP in the Deep South, & then in 1976 the opposite occurred with Carter making massive gains & winning back many Southern White voters. But Carter's Southern gains from 1976 didn't hold, so it's hard to consider it a true Re-Aligning Election:

11. One thing that the graph of county-level trends makes clear is that there has been less & less re-alignment as time has gone on, as counties are increasingly voting similarly from election to election. 2020 actually set a record for the lowest level of county re-alignment:

12. There are small spikes in county voting instability in 2000 & 2016, & I think those two elections have the best argument for a recent re-alignment, w/ the GOP gaining in rural areas (especially the West/South in 2000, & the Midwest/NE in 2016), & Dems w/ urban/suburban voters

13. 2020 saw stabilization in most areas compared to 2016, but Democrats continued to gain with suburban voters (tho they lost ground in some central cities), & Trump continued to make gains in some rural ancestral Dem areas like Eastern IA/OH, suggesting 2016's changes may last:

14. It's always going to be debatable which years are true Re-Aligning Elections, depending on how you define/measure them. But I do think that the years from 1928-1936, 1964, 1980, & both 2000 & 2016 all have good arguments as elections where some major re-alignments occurred.