>>149497557Flamengo is more of a universal club than a prole club. Flamenguistas are everywhere. You find them in every social class and every corner of the country. The association with poor people comes exclusively from their rivalry with Fluminense, who are historically less inclusive and helped cement Flamengo's image as the favelado club.
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>>149497854 said, Flamengo were born in the prestigious homonymous neighbourhood and were in fact close peers with Fluminense before the 1911 schism that created Flamengo's football department. Before that, the same posh kids who played football for Fluminense were also Flamengo members and would row for them.
If we were to be pretentious, Flamengo would be best defined as a corporatist, populist alliance between the dominant classes and the lumpenproletariat. The millions of flamenguistas, many of which are poor, feed the hungry money making machine that keeps the club strong while the club is still managed by members of Rio's elite from the very affluent neighbourhood of Gávea.