Notably, Francisco Gárate, PAN's representative to the state's electoral institute, did not discard the possibility that the PAN candidate will eventually decline in favor of the PRD candidate, should the latter be much further ahead in the polls. This did indeed happen in Guerrero, but PAN is much stronger in Mexico State, and this will not fly well with many of its base members.It's not a surprise that there are people in the party advocating that, but if it happens, this seems like another example of people behind the alliances not being able to pull back and consider the party's interests in a broader context. Obviously, there is a cost in morale among the rank and file and the broader prestige of the party; that cost might be worth it if Eruviel Ávila's election brought us closer to the apocalypse or some other slightly less horrible outcome, but then why is Eruviel Ávila's election so much worse than Alejandro Encinas' from the PAN's perspective? Ideologically, well, it's all a little bit tossed in every direction what with the amorphous and periodically ignored ideology in Mexican political parties, but I don't think anyone would say a longtime AMLO ally from the PRD would be more amenable to PAN beliefs than a mainstream priísta. From the standpoint of removing a cacique through extraordinary political measures, I don't see Mexico State in the same light as Oaxaca and Puebla. Say what you will about Peña Nieto, he wasn't elected fraudulently, nor does he protect pederasts and kidnap journalists who report on it.
The most obvious explanation is that this is a tactical calculation aimed at advancing the PAN's position before the 2012 presidential race. But while Eruviel's defeat may hurt Peña Nieto, who remains the prohibitive favorite, it also helps AMLO. So is delivering a big blow to Peña Nieto worth a big boost for AMLO? If you think it's impossible that AMLO wins in 2012 and that the race is between Peña Nieto and whomever the PAN puts forward, maybe it is. But an AMLO presidency is far worse for the PAN than a Peña Nieto presidency, and the one scenario in which AMLO could potentially do quite well is if the PAN and the PRI had very weak candidates themselves, so that's a big risk to take.