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Understanding Our Election Results Data
Our platform provides deep insights into California's electoral history by solving a common problem: we map historical election results onto current district boundaries. This allows you to see how any of today's districts would have voted in past elections, providing a true apples-to-apples comparison over time.
Our Data Sourcing & Processing
To achieve this, we follow a multi-step process that combines official results with demographic data to ensure accuracy at every level of geography.
1. Source Data: Precinct-Level Results
The foundation of our analysis is the official precinct-level statement of vote for each election, which we source from the California Statewide Database. This raw data shows how many votes each candidate and measure received in every individual precinct across the state.
2. Mapping to Large Districts
For large, standard jurisdictions like entire counties, cities, or state legislative districts, the process is straightforward. We aggregate the results from all the precincts that fall completely within that district's boundaries to produce a total vote count.
3. Estimating for Small & Complex Districts
It gets more complex for small sub-districts (e.g., city council wards) whose boundaries often cut across precinct lines. In these cases, we use a demographic-based estimation method:
- We use U.S. Census block data to identify how the population within a single precinct is distributed geographically.
- If a precinct is split between two sub-districts, we allocate that precinct's votes proportionally based on how many people live on each side of the line.
- This ensures a highly accurate estimate of how a small or irregularly shaped district voted, even when official results are not reported at that level.
What You'll Find: Included Races
Our election analysis covers all recent statewide general and primary elections, including results for:
- Statewide Offices: Governor, Lieutenant Governor, Attorney General, Secretary of State, Controller, and Treasurer.
- Federal Races: President of the United States and U.S. Senate.
- Statewide Propositions: All numbered propositions that appear on the statewide ballot.
Important Caveats & Methodological Notes
Privacy Withholding
To protect voter privacy, counties sometimes withhold results from very small precincts (e.g., under 10 voters). This can occasionally lead to minor discrepancies between our calculated totals and the final official tally, though the difference is almost always negligible.
Estimates vs. Exact Counts
While the vote totals for large, standard districts are exact counts, the totals for smaller, complex sub-districts are technically estimates. However, because they are based on granular census block data, they represent a very close and reliable approximation of the true vote.