Throughout each state in the union, there exist communities whose support a given political party can generally count on. And while each state will have citizens who find themselves at various points on the political spectrum, it's also true that the majority of its citizens can sometimes form an iron-clad voting block.
For instance, political mapping website 270towin has charted three consecutive presidential elections in which California supported the Democratic candidate by over 60%. By a similar token, NBC News reported that the only time Arizona hasn't voted Republican in modern history occurred all the way back in 1952.
Back in 2016, Trump could also largely count on the support of voters aged 65 and over, who favored him over Hillary Clinton by 8 points.
However, it seems that the potential leanings of voters are far more in flux among this demographic in 2020, which could explain emerging Biden support in a Florida community where that may have once seemed unthinkable.