PROBLEM AND OPPORTUNITY In the United States, voting is largely a private matter. A registered voter is given a randomized ballot form or machine to prevent linkage between their voting choices and their identity. This disconnect supports confidence in the election process, but it provides obstacles to an election's analysis. A common solution is to field exit polls, interviewing voters immediately after leaving their polling location. This method is rife with bias, however, and functionally limited in direct demographics data collected. For the 2020 general election, though, most states published their election results for each voting location. These publications were additionally supported by the geographical areas assigned to each location, the voting precincts. As a result, geographic processing can now be applied to project precinct election results onto Census block groups. While precinct have few demographic traits directly, their geographies have characteristics that make them projectable onto U.S. Census geographies. Both state voting precincts and U.S. Census block groups: are exclusive, and do not overlap are adjacent, fully covering their corresponding state and potentially county have roughly the same size in area, population and voter presence Analytically, a projection of local demographics does not allow conclusions about voters themselves. However, the dataset does allow statements related to the geographies that yield voting behavior. One could say, for example, that an area dominated by a particular voting pattern would have mean traits of age, race, income or household structure. The dataset that results from this programming provides voting results allocated by Census block groups. The block group identifier can be joined to Census Decennial and American Community Survey demographic estimates. DATA SOURCES The state election results and geographies have been compiled by Voting and Election Science team on Harvard's dataverse. State voting precincts lie within state and county boundaries. The Census Bureau, on the other hand, publishes its estimates across a variety of geographic definitions including a hierarchy of states, counties, census tracts and block groups. Their definitions can be found here. The geometric shapefiles for each block group are available here. The lowest level of this geography changes often and can obsolesce before the next census survey (Decennial or American Community Survey programs). The second to lowest census level, block groups, have the benefit of both granularity and stability however. The 2020 Decennial survey details US demographics into 217,740 block groups with between a few hundred and a few thousand people. Dataset Structure The dataset's columns include: Column Definition BLOCKGROUP_GEOID 12 digit primary key. Census GEOID of the block group row. This code concatenates: 2 digit state 3 digit county within state 6 digit Census Tract identifier 1 digit Census Block Group identifier within tract STATE State abbreviation, redundent with 2 digit state FIPS code above REP Votes for Republican party candidate for president DEM Votes for Democratic party candidate for president LIB Votes for Libertarian party candidate for president OTH Votes for presidential candidates other than Republican, Democratic or Libertarian AREA square kilometers of area associated with this block group GAP total area of the block group, net of area attributed to voting precincts PRECINCTS Number of voting precincts that intersect this block group ASSUMPTIONS, NOTES AND CONCERNS: Votes are attributed based upon the proportion of the precinct's area that intersects the corresponding block group. Alternative methods are left to the analyst's initiative. 50 states and the District of Columbia are in scope as those U.S. possessions voting in the general election for the U.S. Presidency. Three states did not report their results at the precinct level: South Dakota, Kentucky and West Virginia. A dummy block group is added for each of these states to maintain national totals. These states represent 2.1% of all votes cast. Counties are commonly coded using FIPS codes. However, each election result file may have the county field named differently. Also, three states do not share county definitions - Delaware, Massachusetts, Alaska and the District of Columbia. Block groups may be used to capture geographies that do not have population like bodies of water. As a result, block groups without intersection voting precincts are not uncommon. In the U.S., elections are administered at a state level with the Federal Elections Commission compiling state totals against the Electoral College weights. The states have liberty, though, to define and change their own voting precincts https://en.wikipedia.org/wiki/Electoral_precinct. The Census Bureau... Visit https://dataone.org/datasets/sha256%3A05707c1dc04a814129f751937a6ea56b08413546b18b351a85bc96da16a7f8b5 for complete metadata about this dataset.

Data from https://github.com/TheUpshot/presidential-precinct-map-2020 released under MIT license: https://github.com/TheUpshot/presidential-precinct-map-2020/blob/main/LICENSE. For more detail, see https://www.nytimes.com/interactive/2021/upshot/2020-election-map.html.

Presidential precinct data for the 2020 general election

The Upshot scraped and standardized precinct-level election results from around the country, and joined this tabular data to precinct GIS data to create a nationwide election map. This map does not have full coverage for every state: data availability and caveats for each state are listed below, and statistics about data coverage are available here. We are releasing this map's data for attributed re-use under the MIT license in this repository.

The GeoJSON dataset can be downloaded at: https://int.nyt.com/newsgraphics/elections/map-data/2020/national/precincts-with-results.geojson.gz

Properties on each precinct polygon:

• GEOID: unique identifier for the precinct, formed from the five-digit county FIPS code followed by the precinct name/ID (eg, 30003-08 or 39091-WEST MANSFIELD)
• votes_dem: votes received by Joseph Biden
• votes_rep: votes received by Donald Trump
• votes_total: total votes in the precinct, including for third-party candidates and write-ins
• votes_per_sqkm: total votes divided by the area of the precinct, rounded to one decimal place
• pct_dem_lead: (votes_dem - votes_rep) / (votes_dem + votes_rep), rounded to one decimal place (eg, -21.3)

Due to licensing restrictions, we are unable to include the 2016 election results that appear in our interactive map.

Please contact dear.upshot@nytimes.com if you have any questions about data quality or sourcing, beyond the caveats we describe below.

General caveats

• Where possible, we used official precinct boundaries provided by the states or counties, but in most cases these were not available and we generated boundaries ourselves, using L2 voter-file points to guess the precinct for each census block group; this results in generally accurate precinct boundaries, but can be rough in no- or very-low-population places like business parks or uninhabited rural land.
  • Because of this, spatially joining our precinct GeoJSON to other geographic datasets will most likely yield less-than-ideal output.
• Some of the results we gathered are unofficial/uncertified, since the certified tabulations hadn't yet been released at time of gathering.
• A very small portion of the tabular precinct results (roughly 0.01%) could not be joined to the precinct boundaries, and thus these results are not present in the GeoJSON.
• A few areas, such as rural Maine, Vermont and Hawaii, contain no voters, and those polygons are excluded from the GeoJSON.

State-by-state data availability and caveats

Note: One of the most common causes of precinct data being unusable is "countywide" tabulations. This occurs when a county reports, say, all of its absentee ballots together as a single row in its Excel download (instead of precinct-by-precinct); because we can't attribute those ballots to specific precincts, that means that all precincts in the county will be missing an indeterminite number of votes, and therefore can't be reliably mapped. In these cases, we drop the entire county from our GeoJSON.

• AL: ❌ absentee and provisional results are reported countywide
• AK: ❌ absentee, early, and provisional results are reported district-wide
• AZ: ✅
• AR: ⚠️ we could not generate or procure precinct maps for Jefferson County or Phillips County
• CA: ⚠️ only certain counties report results at the precinct level, additional collection is in progress
• CO: ✅
• CT: ⚠️ township-level results rather than precinct-level results
• DE: ✅
• DC: ✅
• FL: ⚠️ precinct results not yet available statewide
• GA: ✅
• HI: ✅
• ID: ⚠️ many counties ...

This dataset was utilized a join from enriched tables from ESRI which was curated from the 2020 Census from the United States Census Bureau, American Community Survey (ACS) and for voter precinct polygon dataset are from 2024 published by the Secretary of State. This layer has information for all voter precincts within Idaho regarding the total population for 2024. For more information on how the data is curated for the Enrich tool please go the link below. 2024/2029 Esri Updated Demographics

Harris Co. TX commissioner preinct data including 2020 census population demographics. Published to make data available for analysis outside Budget office ATLAS system

This dataset represents the local legislative boundaries of the Lexington-Fayette Urban County Council. The Council districts are determined by the Fayette County Board of Election's voting precinct boundaries and 2010 Census demographic data. Voting precincts are grouped together to create the districts. Updates are made by Lexington-Fayette Urban County Government ordinance approximately every 10 years as new Census data is released in an attempt for population equality in the districts. The districts in this dataset were defined during a series of public meetings held by a Redistricting Committee consisting of 15 appointed members (one community member appointed by each sitting Council Member) and assisted by Lexington-Fayette Urban County Government GIS, Council, and Planning staff as well as the Fayette County Board of Elections. The ordinance for the Council Districts in this dataset received second reading by the Urban County Council on October 27, 2011.

This dataset contains polygons and attributes representing the voting precincts for the counties in the State of Arkansas as represented in the Voting Registration System for each county. It includes the precinct name and number assigned by each County Election Commission following the redistricting process. It also includes Census 2010 and 2020 Voting District Codes. The data was initially generated following the release of the 2010 Census redistricting files. Following the release of the 2020 Census redistricting files, some counties have updated their precincts. This dataset will be updated as we receive new precincts from the Counties following the 2020 Census. Compiling this data is an effort of the Secretary of State to aid in election administration and future redistricting.

The BPDA Research Division prepared Census data on total population, population by race and ethnicity, voting-age population, group quarters populations, and housing occupancy for use in the 2022 City Council redistricting process. These data reflect 2020 census block-level data from the 2020 Decennial Census P.L. 94-171 Redistricting Data aggregated to the 275 precincts (as amended April 6, 2022) and the 9 current City Council Districts. Also included are 2010 estimates for these geographies based on 2010 census block-level.

Notes on coding of Race and Ethnicity:

The data presented here follow the conventions recommended by the Department of Justice in their September 1, 2021 guidance on the use of race and ethnicity data in redistricting. This differs from other commonly reported race and ethnicity groupings in that it groups those reporting 2 races, one White and one non-White, as being members of the non-White race reported. Thus a person reporting White and Black would be categorized here as Black. All residents of Hispanic or Latino origin, regardless of reported race, are grouped together. This coding appears on page 12 of the guidance that can be found here: https://www.justice.gov/opa/press-release/file/1429486/download

Notes on 2010 data:

For 2010 data the BPDA Research Division crosswalked 2010 census block data to 2020 boundaries using a combination of block assignment and areal interpolation based on Census Tiger shapefiles and the publicly available boundary files for Boston electoral geographies. For blocks split across 2020 boundaries the entire 2010 population was assigned to one side of the boundary if no residential structures within that block existed on the other side of the boundary. In cases where residential structures were present on both sides of the boundary, areal interpolation was used to assign the block's population and housing units based on the share of the land area of the block falling on either side of the boundary. These numbers will differ from those produced using different crosswalking methods.

This dataset was utilized a join from enriched tables from ESRI which was curated from the 2020 Census from the United States Census Bureau, American Community Survey (ACS) and for voter precinct polygon dataset are from 2024 published by the Secretary of State. This layer has information for all voter precincts within Idaho regarding the population by age language spoken at home for 2022. For more information on how the data is curated for the Enrich tool please go the link below. 2024/2029 Esri Updated Demographics

Election Districts and Precincts dataset current as of 2013. Wards serve as administrative subunits that are aggregated into election districts of equal population..

This dataset was utilized a join from enriched tables from ESRI which was curated from the 2020 Census from the United States Census Bureau, American Community Survey (ACS) and for voter precinct polygon dataset are from 2024 published by the Secretary of State. This layer has information for all voter precincts within Idaho regarding the population poverty index for 2022. For more information on how the data is curated for the Enrich tool please go the link below. 2024/2029 Esri Updated Demographics