Anthony Quezada gives a victory speech at a watch party in Portage Park after winning a five-way race for Cook County Board of Commissioners 8th District. [Erin Hegarty/The Daily Line]

The Cook County Board of Commissioners’ left flank is set to be shored up next year as Anthony Quezada, a Northwest Side political organizer and longtime right hand to Chicago Ald. Carlos Ramirez-Rosa (35), jumped ahead of a crowded field to unseat two-term Comm. Luis Arroyo, Jr.

At the same time, a dyed-in-the-wool conservative took his place as the Republican Party’s nominee to succeed the retiring moderate Comm. Pete Silvestri (R-9), setting the stage for deeper polarization on the Democrat-dominated board responsible for setting the county’s $8 billion budget.