California's political landscape is defined by overlapping jurisdictions—geographic boundaries that layer on top of each other, each with its own elected officials, voters, and political dynamics. Understanding this structure is essential for interpreting the data on this platform.
Finding and Navigating Jurisdiction Pages
Before diving into concepts, let's orient you to how the platform is organized. Open San Luis Obispo in a new tab to follow along—we'll use it as our reference throughout this guide.
Finding a jurisdiction:
- Search: Click the search icon in the sidebar and type a name—city, county, or district
- Browse: In the sidebar, go to Local → Places → Cities (or Counties, School Districts) to see lists you can filter and explore
The jurisdiction page structure:
Every jurisdiction page has a navigation bar with dropdown menus. The Home icon returns you to the Summary page.
- Summary (Home icon): The default landing page showing registration breakdown, partisan lean, and key characteristics at a glance
- Overview: Elected officials, overlapping districts, and (for counties) sub-jurisdictions
- Campaign Finance: Committees, Form 460s, independent expenditures, and late contributions (available for jurisdictions that file electronically)
- Candidates: Declared candidates for upcoming local races (when available)
- Voters: Voter metrics (registration, turnout, projections), census data (demographics, education, income, housing), and ideology analysis
- Elections: Historical election results and precinct-level analysis tools
Throughout this guide and others, when we reference navigation like "check Overlapping Districts" or "go to Voters → Voter Metrics → Turnout," we're referring to these menus on a jurisdiction page—not the main sidebar.
The Layering Principle
Every California voter simultaneously belongs to multiple jurisdictions:
- County (58 total)
- City (or unincorporated county area)
- Congressional District (52 districts)
- State Senate District (40 districts)
- State Assembly District (80 districts)
- Board of Equalization District (4 districts)
- School District (often multiple: elementary, high school, community college)
This means a single voter in San Francisco might be represented by a city council member, a county supervisor (same person in SF's case), an Assembly member, a State Senator, a Congress member, and multiple school board members—all at once.
Why Overlapping Matters
Different voter pools, different politics. An Assembly district might span parts of three cities with very different political compositions. The district's overall lean is a blend—not a simple average—of these communities.
Shared constituencies create relationships. A State Senator whose district overlaps with three Assembly districts has natural relationships (and sometimes rivalries) with those Assembly members. They share some voters but not others.
Local context shapes statewide races. A Congressional candidate in a district that includes both urban Oakland and suburban Contra Costa communities must appeal to voters with different priorities. Understanding where the votes are—geographically—is crucial.
Finding Overlapping District Data
On any jurisdiction page, click the Overlapping Districts tab to see which other jurisdictions share voters with the one you're viewing. If you're looking at Assembly District 15, you can see which cities, counties, and Congressional districts overlap with it.
Summary pages (the default view for any jurisdiction) show the political profile—registration breakdown, partisan lean, and key characteristics.
Precinct-level maps are available on jurisdiction pages under the Elections tab—click into any election result to see the map. These show exactly where political support varies within a jurisdiction.
Redistricting and Map Versions
California redistricts every 10 years following the census. This platform uses the 2022-2032 district maps, including the approved Congressional maps that take effect in 2026.
Historical election results are available for earlier periods, though displayed without the underlying district geography. When analyzing trends across redistricting cycles, keep in mind that district boundaries—and therefore the voters within them—may have changed significantly.
Practical Applications
Researching a race: Start with the jurisdiction's Summary page, then check Overlapping Districts to understand the political landscape. A competitive Assembly race might hinge on turnout in specific cities within the district.
Understanding endorsements: When a city council member endorses a Congressional candidate, check whether that city falls within the Congressional district. Local endorsements from outside the district have less practical impact.
Targeting outreach: If you're working on a campaign, overlapping district analysis helps identify which communities are "in play" versus reliably partisan. You'll find the swing precincts where persuasion matters most.
Following the money: Campaign contributions often flow along jurisdictional lines. A County Supervisor running for Assembly will likely have donors from their county who are also in the Assembly district.
Key Concepts to Remember
Jurisdiction types serve different functions. Counties handle services like elections and public health. Cities handle local land use and police. State legislative districts exist solely for representation—they don't provide services.
Population differs from registered voters. A jurisdiction's population includes everyone—children, non-citizens, people who haven't registered. Registered voters are a subset, and actual voters in any given election are a smaller subset still.
Geography is not destiny. While certain areas lean Democratic or Republican, the margin matters as much as the direction. A district that's D+5 behaves very differently from one that's D+25.
Understanding California's political geography transforms raw data into actionable intelligence. Instead of seeing isolated numbers, you'll see how jurisdictions connect, overlap, and influence each other—revealing the true shape of the state's political landscape.