This book is a Brazilian study that used the Agenda-Setting hypothesis. This hypothesis was created in the early 1970s, based on journalistic coverage of the presidential elections that took place at the end of the 1960s in the United States. Agenda-setting celebrated its 40th anniversary in 2011 and has been researched in various parts of the world. This research, which I am publishing in book format, was defended as a Master's Dissertation at the Pontifical Catholic University of Rio Grande do Sul.