Brazilians are about 50%-60% Catholic Roman. The percentage used to be higher still. To this day we are presumed to be Catholics until we signal otherwise. It is far more usual for Catholics to have been raised into the creed than to actively choose to adhere. In absolute numbers, we are the largest Catholic contingent worldwide, although Mexico comes close and may well surpass us in the near future.
The average Brazilian has very little awareness of other religions and creeds, being generally aware of Kardecist Spiritism, a spectrum of Protestant beliefs including very influential neo-charismatic churches (usually called "Evangelicals"), assorted other Christian groups, the African origin religions Umbanda and Candomblé and perhaps Seicho-no-Ie and Christian Orthodox churches, the last two perceived as largely ethnic beliefs.
Most Brazilians have a measure of a syncretic attitude towards religion. It is frowned upon to be openly atheistic here, and neo-charismatics can be intolerant, but other than that people rarely want to question anyone else's beliefs. Catholicism is widely perceived as an unremarkable "default" belief, while Spiritism is often perceived (despite being very animistic and reincarnationist in nature) as an extension or bridge from Catholicism into something wider - sometimes a bolder form of Catholicism, sometimes a creed that dares to ask and answer questions. Meanwhile, Umbanda and Candomblé have to deal with a lot of largely undeserved prejudice and mistrust.
In practice Catholicism's role in Brazilian society is mainly not to be perceived as true in a doctrinary sense, but rather as a respectable and useful institution, to the point of not being questioned too directly nor too often. Which is one reason why it has been losing adherents to other creeds (mostly Neo-Charismatics) at a significant rate. Neo-Charismatics tend to make very specific promises for significant personal change right here in this world. Catholics, not so much.
Catholicism in Brazil also suffers from a very significant self-inflicted internal tension. On the one hand it has a clear doctrine that requires very specific and fairly unusual beliefs; on the other, it is rather more interested in being accepted and heard than in asking whether we truly believe. I am not the exception among Brazilian atheists for having been through Eucharist despite never having been a believer.
In practice, Catholicism as it exists in Brazil is a wide alliance of people with various degrees of interest in the actual doctrine and the political and social visibility and influence of the church. At present it does not have too much of a clear political stance and is in fact fractured to a significant degree. Parts of it flirt continuously with Fascism, others are interested in social justice.
It has largely lost its arrogance, which is one reason why the Neo-Charismatics are currently far more influential in politics. Another is that there isn't much of a consensual political goal among Catholics.
But for decades now, Catholicism in Brazil cares a lot more about reverence than about belief. Which is arguably a good thing.
