The survey of the Center for Public Studies zip with a sampling error estimate of 3.0% and 95% confidence percentage is one of the most reliable studies when measuring the national political developments. The survey of the months' May-June "2009, one of three set for this year, fifteen hundred people consulted in 146 communes in the country, carrying a major impact on the presidential race. As a result the question "Who would you vote? Piñera figure at 37%, 30% Frei, Marco Enriquez Ominami 13% and candidates Juntos Podemos, Jorge Arrate, the MAS Alejandro Navarro Adolfo Zaldivar and PRI marginal result of 1.0%. These data triggered a series of political movements and strategies for the next presidential election is worth record.

1. The Evolution of Frei's Candidacy

Faced with the question posed to respondents enrolled in the voter list on who you think will be the next President, the flag bearer of the right totaled 45%, Frei gets 36% and Enriquez Ominami who had not appeared previously in this item, you get 3.0%.'s important is the change which has the same question between the measurements of November-December 2008 and May-June 2009 in which Piñera low of 51% to 47% and rises explosively Frei of a 5 % to 35% made that gives the best performance of presidential policy and shortens the distance with Piñera leaving it in a dead heat in the presidential runoff.

2.La evolution of the nomination of Enriquez-Ominami

One of the most desired was to know the evolution of the candidacy of Marco Enríquez-Ominami against that of Eduardo Frei Ruiz-Tagle, because telephone surveys before the CEP ventured a possible tie of forces between these candidates. This did not happen and the support to consign CEP Enriquez-Ominami of 13% of accessions that although considerable support in comparison to the other candidates left sideline receiving support from 1% however, still a determining factor in the presidential process and predicted the most enthusiastic adherents.