Another underrated one:
Liberal whites do not really have many kids anymore and tend not to marry until very late in life, while conservative whites are still having a lot of babies.
This one deserves a lot more attention than it's getting. Although I do suspect it's easier to pass all your political values on to an only child than to all 4 of your children at once. The large families probably have a lot more who switch sides when they come of age.
I feel like this is both over and under rated.
Conservative birth rate is underrated by liberals, because, I think frankly the sort of person who is inclined to have six kids can't afford to live in a high cost of living area, and is going to follow a very different life pattern than the typical white liberal.
However it's also overrated by conservatives, overestimate the difference in birth rates and the role retention rates play. The typical fundamentalist or Evangelical birth rate is only marginally above average.
It's a sort of open secret that conservative Christians aren't that different from their secular counterparts. Some conservatives seem to have images of Israel where a birth rate of 6 vs 2 in the average population allowed the Hasidic population to swell in a few generations. Those people exist in America, but they are a very small portion of Evangelicals, and it will take a long time for that birth differential to have a noticeable effect.
Interesting, so religious minority birthrates are still notably higher than white fundamentalist Protestant birthrates and even the gap between white fundamentalist Protestant vs. no religion is still only about 0.5 children per family. And white Christian liberals, who are only off by 0.2-0.3 children are likely still a larger group than white atheist/agnostic liberals. It's certainly not a 3.5 kids/family vs. 1 kid/family situation in aggregate. That does throw a wrench into the theory that differential birth rates are what is pulling the white population rightward (if the white population even is still moving rightward post 2012).
I do think differential birthrates could explain why traditional gender roles have been more resilient than most people expected they would be in the 1980's/90's though. That is something that people do seem to model after their parents, but it also isn't a direct correlation with D vs. R politics (some very Dem minority groups are more traditionalist on these issues).
