This is a data package for R containing the results of statewide elections in NJ, from 2004 to 2021.
You can install the development version of njelections like so:
# install.packages("devtools")
devtools::install_github("tor-gu/njelections")This package contains the results of statewide general elections for three offices:
- New Jersey Governor
- US Senate
- US President
All elections from 2004 to 2021 are included, at three levels of organization:
- Statewide (
election_statewide) - By county (
election_by_county) - By municipality (
election_by_municipality)
Table election_statewide contains the following columns, which are
common to all tables in this dataset:
| Field | Type | Description | Example |
|---|---|---|---|
| year | int | Election year | 2004 |
| type | chr | Currently always ‘General’ | General |
| office | chr | ‘President’, ‘Senate’, or ‘Governor’ | President |
| candidate | chr | Candidate name | John F. Kerry |
| party | chr | Candidate party | Democratic |
| vote | int | Number of votes received | 1911430 |
There is one row in this table for every year, office, and
candidate combination.
| year | type | office | candidate | party | vote |
|---|---|---|---|---|---|
| 2004 | General | President | John F. Kerry | Democratic | 1911430 |
| 2004 | General | President | George W. Bush | Republican | 1670003 |
| 2004 | General | President | Ralph Nader | Independent | 19418 |
Table election_by_county contains all of the columns in
election_statewide, plus two more:
| Field | Type | Description | Example |
|---|---|---|---|
| GEOID | chr | US Census GEOID for the county | 34001 |
| county | chr | County name | Atlantic County |
There is one row in this table for every year, office, county and
candidate combination. In particular, for a given year and office,
every candidate is represented in every county.
| year | type | office | GEOID | county | candidate | party | vote |
|---|---|---|---|---|---|---|---|
| 2004 | General | President | 34001 | Atlantic County | John F. Kerry | Democratic | 55746 |
| 2004 | General | President | 34003 | Bergen County | John F. Kerry | Democratic | 207666 |
| 2004 | General | President | 34005 | Burlington County | John F. Kerry | Democratic | 110411 |
Table election_by_municipality contains all of the columns in
election_statewide, plus three more:
| Field | Type | Description | Example |
|---|---|---|---|
| GEOID | chr | US Census GEOID for the municipality | 3400100100 |
| county | chr | County name | Atlantic County |
| municipality | chr | Municipality name | Absecon city |
There is one row in this table for every year, office, county,
municipality and candidate combination. In particular, for a given
year and office, every candidate is represented in every
municipality.
| year | type | office | GEOID | county | municipality | candidate | party | vote |
|---|---|---|---|---|---|---|---|---|
| 2004 | General | President | 3400100100 | Atlantic County | Absecon city | John F. Kerry | Democratic | 1800 |
| 2004 | General | President | 3400100100 | Atlantic County | Absecon city | George W. Bush | Republican | 2177 |
| 2004 | General | President | 3400100100 | Atlantic County | Absecon city | Ralph Nader | Independent | 25 |
The source for this data is the New Jersey Division of Elections. The data was derived by scraping the PDFs in the election results archive.
New Jersey municipalities have not been stable over the course of 2004-2021:
- Several municipalities have changed names or been assigned new GEOIDs by the US Census.
- In 2013, Princeton borough and Princeton township merged
The njmunicipalities
package contains municipality names and GEOIDs across the period
2001-2021. The election_by_municipality table uses the names and
GEOIDs from the njmunicipalities package for the year of the election,
with the exception of the Princetons
for the 2012 election. See Accounting for changing municipal
names for a worked example
dealing with these issues.
At the time of the 2012 election, Princeton borough and Princeton township were still separate municipalities. However, the official results for Mercer County provide only the combined results for the merged Princeton municipalities.
As a result, the election_by_municipality table uses the 2013
municipality list from njmunicipalities for the 2012 election. The
Princeton merger is the only difference in the 2012 and 2013
municipality list.
In general, an attempt was made to record candidate and party names exactly as they appear in the official results. However, when the same candidate or party appears in multiple elections with slightly varying names, the most common form of the name was used.
For example, Jeff Boss has appeared in official results variously as ‘Jeff Boss’, ‘Jeffrey Boss’ and ‘Jeffery “Jeff” Boss’. In this package, his name has been standardized to “Jeff Boss”.
Similarly, the Green and Libertarian party names have been standardized to “Green Party” and “Libertarian Party”.
When a candidate does not have a listed party, the party is recorded as “Independent”.
For every year, office and candidate combination, the vote total
across counties exactly matches the vote total in the statewide results:
library(dplyr)
# Statewide election matches sum of county votes for every year and every office
election_by_county |>
group_by(year, type, office, candidate) |>
summarize(county_vote = sum(vote), .groups = "drop") |>
left_join(election_statewide,
by = c("year", "type", "office", "candidate")) |>
filter(vote != county_vote) |>
nrow()
#> [1] 0The sum across municipalities does not always match the county total. In many – but not all – cases, the official county results account for the discrepancy. For example, the official 2020 Presidential results from Morris County include federal overseas votes in a separate row, not assigned to any municipality. These discrepancies, even when explicitly included in the official results, are not recorded in this package.
library(dplyr)
library(tidyr)
library(njelections)
hudson_senate_2012 <- election_by_municipality |>
filter(year == 2012,
office == "Senate",
county == "Hudson County") |>
select(GEOID, municipality, party, vote) |>
pivot_wider(names_from = party, values_from = vote) |>
select(GEOID, municipality, Democratic, Republican,
Libertarian = `Libertarian Party`, Green = `Green Party`)| GEOID | municipality | Democratic | Republican | Libertarian | Green |
|---|---|---|---|---|---|
| 3401703580 | Bayonne city | 12735 | 5067 | 98 | 166 |
| 3401719360 | East Newark borough | 356 | 59 | 2 | 1 |
| 3401728650 | Guttenberg town | 2366 | 500 | 20 | 18 |
| 3401730210 | Harrison town | 2458 | 520 | 22 | 31 |
| 3401732250 | Hoboken city | 12819 | 5695 | 210 | 184 |
| 3401736000 | Jersey City city | 56469 | 8077 | 414 | 565 |
| 3401736510 | Kearny town | 6706 | 2559 | 52 | 93 |
| 3401752470 | North Bergen township | 15187 | 3196 | 54 | 100 |
| 3401766570 | Secaucus town | 3940 | 1942 | 21 | 37 |
| 3401774630 | Union City city | 14094 | 2169 | 56 | 79 |
| 3401777930 | Weehawken township | 3429 | 915 | 41 | 55 |
| 3401779610 | West New York town | 9166 | 2139 | 26 | 60 |
Over the period 2004-2021, several municipalities changed names and
GEOIDs, and Princeton township was merged into Princeton borough. The
package njmunicipalities
is helpful here.
As an example, let consider Mercer county, which includes the merged Princetons, as well as Robbinsville township, previously known as Washington township. Let’s plot the two-party share of votes for each municipality in Mercer, using the current name for each municipality, and combining the totals for the Princetons in the years prior to the merger.
First, generate a cross reference table for the GEOIDs, using the 2021
GEOIDs and municipality names as the reference. We use
njmunicipalities::get_geoid_cross_reference and
njmunicipalities::get_municipalities for this.
library(njmunicipalities)
geoid_xref <- get_geoid_cross_references(2021, 2004:2021) |>
dplyr::filter(!is.na(GEOID_ref)) |>
dplyr::left_join(get_municipalities(2021), by = c("GEOID_ref" = "GEOID"))| year | GEOID_ref | GEOID | county | municipality |
|---|---|---|---|---|
| 2004 | 3400100100 | 3400100100 | Atlantic County | Absecon city |
| 2004 | 3400102080 | 3400102080 | Atlantic County | Atlantic City city |
| 2004 | 3400107810 | 3400107810 | Atlantic County | Brigantine city |
| 2004 | 3400108680 | 3400108680 | Atlantic County | Buena borough |
| 2004 | 3400108710 | 3400108710 | Atlantic County | Buena Vista township |
Now, generate the two-party share of the vote, combining Princeton
borough and township. The constants PRINCETON_TWP_GEOID and
PRINCETON_BORO_GEOID come from njmunicipalities.
tpsov <- njelections::election_by_municipality |>
dplyr::mutate(GEOID = dplyr::if_else(GEOID == PRINCETON_TWP_GEOID,
PRINCETON_BORO_GEOID,
GEOID)) |>
dplyr::group_by(year, office, GEOID, party) |>
dplyr::summarize(vote = sum(vote), .groups = "drop") |>
dplyr::filter(party %in% c("Democratic", "Republican")) |>
dplyr::group_by(year, office, GEOID) |>
dplyr::summarize(party = party,
two_party_share_of_vote = vote/sum(vote), .groups="drop")| year | office | GEOID | party | two_party_share_of_vote |
|---|---|---|---|---|
| 2004 | President | 3400100100 | Democratic | 0.4526025 |
| 2004 | President | 3400100100 | Republican | 0.5473975 |
| 2004 | President | 3400102080 | Democratic | 0.7595311 |
| 2004 | President | 3400102080 | Republican | 0.2404689 |
| 2004 | President | 3400107810 | Democratic | 0.4536190 |
Finally, combine the two tables and plot.
library(ggplot2)
tpsov |>
dplyr::left_join(geoid_xref, by = c("year", "GEOID")) |>
dplyr::filter(county == "Mercer County") |>
ggplot(aes(x = year, y = two_party_share_of_vote, color = party)) +
scale_color_manual(values = c("Democratic" = "blue", "Republican" = "red")) +
geom_point() +
geom_smooth(se = FALSE, formula = y ~ x, method = "loess") +
facet_wrap("municipality") +
ylab("Two party share of vote") +
xlab("Election year") +
labs(title = "Mercer County, NJ, two party share of vote",
subtitle = "US Senate, President and Governor races, 2004-2021")