Grounded in the theory of intra-media agenda-setting, this research will analyze the dynamic process among the Mexican national television networks during the 2006 presidential election campaign period. Specifically, what were the intra-media agenda-setting effects between the Mexican television media Televisa and TV Azteca during the 2006 presidential election campaign? The television content analysis data set is from a systematic random sample of national Mexican prime time television news programs broadcast during the official Instituto Federal Electoral's (Federal Electoral Institute) presidential campaign period, which runs from January 19 to June 28, 2006. The Mexican television newscasts that were analyzed are Televisa's El Noticiero con Joaquín López Dóriga, and TV Azteca's Hechos de la Noche. Overall, the results indicated that television news strongly influences a presidential candidate's television political spots. The flow of communication between television news and a candidate’s television political spots was scrutinized in several time frames in order to examine the influence from a general perspective (3 months, then 2 months) into a specific (month by month) perspective. The outcome at the 3-month scale indicated that television news strongly influenced a candidate’s political spots. The same pattern was observed at the two-month interval. Finally, the month-by month outcome also indicated that television news influenced a candidate’s political spots. / text