Complex sentence: The Houses ("As Casas "), which are closely affiliated with the"sócios", are fan-clubs which have an eligible vote decided by the House leaders; and the ordinary fans of the club, who do not possess any formal membership.
Split into simpler sentences: The Houses ("As Casas "), which are closely affiliated with the"sócios", are fan-clubs which have an eligible vote decided by the House leaders. Lastly, there are the ordinary fans of the club, who do not possess any formal membership.