So here's what I can say about the Portuguese-American population (which makes up a significant portion of the folks in these two towns, although Hispanics are pretty prominent in New Bedford too).
-In Fall River and New Bedford, the Portuguese are blue-collar and often lack college degrees. Demographically that lines up with national trends.
-The Lusophone population is VERY Catholic. Lots of socially conservative Democrats, represented well by Alain Silvia. The Democrats' leftward lurch doesn't play well with older Catholic ethnics.
-At least in MA and RI, Portuguese-Americans came a little later than Italians or Irish did (contrast that with California where they're more rooted). They started off more Democratic in recent times and while some swung GOP in 2016, there was greater room for Democrats to fall due to more old-school loyalty and less assimilation. We tend to be a little more insular than groups who have been here for a long time.
I remember telling a (will not name them) Portuguese-American state representative in 2018 that I was a little concerned about the Republicans making inroads after 2016's enormous swing. This person basically brushed it off and yet here we are with another huge swing in 2020...
