popular organization and democracy in rio de janeiro: a tale of two favelas, by robert gay is an impressive work that illustrates two different favelas' approaches to involvement in rio's political process.

while vila brasil, a favela in the zona oeste of rio, survives by exchanging votes for basic concessions, the favela vidigal, in rio's zona sul, refuses to support any political candidate who does not address wages, education, and health care.

the book also examines the relationship of the poor and the political elite during the late 70's and early 80's, which was a time of significant transformation in rio's history.  this book is available on google books, and it can be read here.