We all like to look at California politics by who wins and who loses.  Democrats win here, Republicans win there (albeit fewer of them), but this doesn’t always tell us what Californians actually think when they vote.  Ballot measure results help, but it is still an incomplete picture.  Even within important categories like party registration and ethnicity, there is a great deal of ideological diversity.  Understanding the nuances of how people think can greatly affect how academics, consultants, and political watchers view the statewide electorate.

The California Political Precinct Index (CPPI) is single-number political index of nearly every voting precinct in California – over 20,000 in all.  This index was first created this in 2007, but after revising the methodology on joining precincts from year to year, we have a new 2012 version below that provides the highest-resolution look available of the California political picture.

The index itself is a 0-100 scale of the ideological leaning of a precinct, where lower numbers represent the most conservative precincts and higher numbers represent the most liberal precincts.  The CPPI is created from an algorithm using several ballot measures over the 2008 and 2010 elections.  These ballot measures, like same-sex marriage and alternative fuel bonds, have clear left-right ideological underpinnings that nearly all people working in politics understand.

The CPPI can be used to measure many aspects of the California electorate, by looking at election results, or by correlating it with countless demographic or registration categories.  These are some of the things we found:

Soon, we’re going to be looking at the new Assembly, Senate, and Congressional lines to help predict how the primary elections are going to go.  We’ll also be able to estimate which parts of the state will support the various fiscal measures we’ll be seeing this fall.  Having the CPPI adds a powerful new tool to help understand California’s complex political landscape.


The link to the original CPPI report can be found here.