The 2012 PNP Primary for HD-4, a contest between Former municipal legislator and Incumbent Rep Liza Fernández's office's executive director Victor Páres and former San Juan I senator/HD-05 Representative Carlos Díaz resulted in Victor Parés comfortably landsliding Díaz to become the PNP nominee for HD-04.
Here, Institutional support from San Juan Mayor Jorge Santini and Fernández allowed Parés to lock up the seat early on, with Carlos Díaz—who lost renomination in 2008 to senator Kimmey Raschke Martínez—only attaining 31% of the vote to Paré's 67%.
Díaz would later become a member of the PPD — running in and losing in the At-Large Senate primaries for that party in 2024.