A recent piece in the New York Times says "In 1960, about 4 percent of Americans said they would be displeased if their child married someone from the other party. By 2020, that had grown to nearly four in 10. Indeed, only about 4 percent of all marriages today are between a Republican and a Democrat." That is, they included a link to the source of the second piece of information, but not the first and the third. But my standards of what's fit to link are lower, so I'll try to provide them.
The first is from The Civic Culture, by Gabriel Almond and Sidney Verba, but the third was new to me. Ideally, you would have a survey that had separate interviews of both members of married couples, but there aren't many like that, so I looked for surveys that asked people about spouse's politics. I couldn't find any that asked about their spouse's party identification or registration, but there was one from 2016 (just after the election) that asked people about how they and their spouse had voted. There were also some earlier surveys that had parallel questions. The results:
Same Different Ratio
1944 72% 4% 18
1960 67% 5% 13.4
1984 64% 6% 10.7
2016 63% 4% 15.8
[2016 68% 10%] 6.8
Although I can't be sure, I'd guess that the 2016 survey was the source of the statement in the Times. In any case, it makes it possible to compare things to the past. In 1944, 1960, and 1984, almost all votes were for the Democratic or Republican candidate--the columns don't add to 100 because some people said that their spouse hadn't voted and others didn't know how they'd voted. But in 2016, about 6% of the vote went to other candidates, and the figures in brackets include those votes. If you don't count the 2016 "others," there's no clear pattern--the samples are only one or two thousand, so there's a good deal of sampling error. If you count the "others," there was more intra-marriage disagreement in 2016 than in earlier elections. But maybe at least some of those should be counted as intermediate (e. g., one for Trump, one a write-in) rather than disagreement? I won't get into that--I'll just observe that the surveys don't provide evidence that married couples are more likely to vote the same way now as they were in the middle of the 20th century. But what about the question about how you would feel if a child married someone from the other party, where there is evidence of change? I'll consider that in a future post.
[Data from the Roper Center for Public Opinion Research]
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