I don't know a lot about Brazil, so someone may correct me, but I'm under the impression that crime in Brazilian cities can be quite bad.

This is a big reason. Another is a feeling, common in better developed regions, that their tax money is being used to sustain regions that "don't pull their weight"

Source: lived in Brazil for 5 years

It’s not that clear-cut, in the richest states in the South the pattern is similar to what you see in the US, urban left, rural right.

Also, this election is not typical. Left or centre-left has won 6 ou of the 7 past presidential elections since the end of military rule. Brazil, like most Latin American countries, is predominantly left-leaning. Bolsonaro has been an anomaly and most likely will not be reelected.

I don't think any is obvious.

But there are different views about urban violence (what is a huge talking point of Bolsonaro), different ways people get their news, urban community breakdown, different religious trends, and a lot more.