# Jefferson County, Missouri

Jefferson County is located in the eastern portion of the U.S. state of Missouri. It is a part of the St. Louis Metropolitan Area. As of the 2020 census, the population was 226,739, making it the sixth-most populous county in Missouri. Its county seat is Hillsboro. The county was organized in 1818 and named in honor of former president Thomas Jefferson. In 1980, according to the U.S. census held that year, the county contained the mean center of U.S. population. Notably, this was the first census in which the center of population was west of the Mississippi River. Jefferson County is part of the St. Louis Metropolitan Statistical Area and encompasses many of the city's southern suburbs.

## Geography

According to the U.S. Census Bureau, the county has a total area of 664 square miles (1,720 km$^2$), of which 657 square miles (1,700 km$^2$) is land and 7.7 square miles (20 km$^2$) (1.2%) is water. The county's eastern border is the Mississippi River.

### Adjacent counties

* St. Louis County (north)
* Monroe County, Illinois (east)
* Ste. Genevieve County (southeast)
* St. Francois County (south)
* Washington County (southwest)
* Franklin County (west)

### Major highways

* Interstate 55
* U.S. Route 61
* U.S. Route 67
* Route 21
* Route 30
* Route 109
* Route 110
* Route 141
* Route 231

### National protected area

* Middle Mississippi River National Wildlife Refuge (part)

## Demographics

As of the 2020 census, Jefferson County had a population of 226,739. The ethnic and racial makeup of the county was 90.4% white (89.7% non-Hispanic white), 1.0% black or African American, 0.3% American Indian, 0.8% Asian, 0.8% some other race, and 6.6% two or more races. 2.4% of the population was of Hispanic or Latino origin.
As of the 2010 census, Jefferson County had a population of 218,733. The reported ethnic and racial make up of the population was 95.4% non-Hispanic white, 0.8% African-American, 0.3% Native American, 0.6% Asian, 0.4% reporting some other race, 1.3% reporting two or more races and 1.6% Hispanic or Latino of any race.
As of the census of 2000, there were 198,099 people, 71,499 households, and 54,553 families residing in the county. The population density was 302 inhabitants per square mile (117/km$^2$). There were 75,586 housing units at an average density of 115 units per square mile (44/km$^2$). The racial makeup of the county was 97.48% White, 0.68% Black or African American, 0.29% Native American, 0.36% Asian, 0.01% Pacific Islander, 0.24% from other races, and 0.93% from two or more races. Approximately 1.01% of the population were Hispanic or Latino of any race.
There were 71,499 households, out of which 38.90% had children under the age of 18 living with them, 61.00% were married couples living together, 10.40% had a female householder with no husband present, and 23.70% were non-families. 18.90% of all households were made up of individuals, and 6.10% had someone living alone who was 65 years of age or older. The average household size was 2.74 and the average family size was 3.12.
In the county, the population was spread out, with 27.90% under the age of 18, 8.50% from 18 to 24, 31.80% from 25 to 44, 22.50% from 45 to 64, and 9.20% who were 65 years of age or older. The median age was 35 years. For every 100 females there were 98.90 males. For every 100 females age 18 and over, there were 95.90 males.
The median income for a household in the county was $60,636, and the median income for a family was $66,697. Males had a median income of $37,822 versus $25,440 for females. The per capita income for the county was $25,058. About 4.90% of families and 6.80% of the population were below the poverty line, including 8.10% of those under age 18 and 6.30% of those age 65 or over.
There were 146,316 registered voters in 2008. As of October 24, 2012, there were 148,011.

### 2020 census

Jefferson County Racial Composition :
| Race | Num. | Perc. |
| White (NH) | 203,287 | 89.66% |
| Black or African American (NH) | 2,295 | 1% |
| Native American (NH) | 617 | 0.27% |
| Asian (NH) | 1,839 | 0.81% |
| Pacific Islander (NH) | 71 | 0.03% |
| Other/Mixed (NH) | 13,078 | 5.77% |
| Hispanic or Latino | 5,552 | 2.45% |

## Education
### Public schools

* School District 47 - Crystal City
** Crystal City High School - Crystal City
* De Soto School District 73 - De Soto
** Early Childhood Center (PK)
** Athena Elementary School (K-06)
** Vineland Elementary School (K-06)
** De Soto Jr. High School (07-08)
** De Soto High School (09-12)
* Dunklin R-V School District - Herculaneum
* Festus R-IV School District - Festus
** Festus Elementary School (K-03)
** Festus Intermediate School (04-06)
** Festus Middle School (07-08)
** Festus High School (09-12)
* Fox C-6 School District - Arnold
* Grandview R-II School District - Hillsboro
** Grandview Elementary School (K-05) - Hillsboro
** Grandview Middle School (06-08) - Hillsboro
** Grandview High School (09-12) - Ware
* Hillsboro R-3 School District - Hillsboro
** Hillsboro Primary School (K-02)
** Hillsboro Elementary School (03-04)
** Hillsboro Middle School (05-06)
** Hillsboro Jr. High School (07-08)
** Hillsboro High School (09-12)
* Jefferson County R-VII School District - Festus
** Plattin Primary School (PK-02) - Plattin
** Telegraph Intermediate School (03-05) - Festus
** Danby-Rush Tower Middle School (06-08) - Festus
** Jefferson High School- Festus
* Northwest R-I School District - High Ridge
** Brennan Woods Elementary School (K-05) - High Ridge
** Cedar Springs Elementary School (K-05) - House Springs
** High Ridge Elementary School (K-05) - High Ridge
** House Springs Elementary School (K-05) - House Springs
** Maple Grove Elementary School (K-05) - Dittmer
** Murphy Elementary School (K-05) - High Ridge
** Woodridge Middle School (06-08) - High Ridge
** Valley Middle School (06-08) - House Springs
** Northwest High School (09-12) - Cedar Hill
* Sunrise R-IX School District - De Soto
** Sunrise Elementary School (K-08) - De Soto
* Windsor C-1 School District - Imperial

### Private schools

* Christian Outreach School (K-12) - Hillsboro - Nondenominational Christian
* People's Christian Academy (K-12) - Arnold - Assembly of God/Pentecostal
* St. Pius X High School (09-12) - Festus - Roman Catholic
* Twin City Christian Academy (PK-12) - Festus - Baptist
* Good Shepherd Catholic School - (K-08) - Hillsboro - Roman Catholic
* Holy Child Elementary & Middle School - Arnold - (K-08) - Roman Catholic
* Manna Christian Academy - De Soto - (K-12) - Southern Baptist
* Our Lady's Catholic School - Festus - (K-08) - Roman Catholic
* Sacred Heart Catholic School - Festus - (K-08) - Roman Catholic
* St. Anthony's Catholic School - High Ridge - (K-08) - Roman Catholic
* St. Joseph's Catholic School - Imperial - (K-08) - Roman Catholic
* St. Johns Lutheran School - Arnold - (PK-08) - Lutheran
* St. Johns School - Imperial - (K-08) - Nondenominational Christianity
* St. Rose of Lima Catholic School - De Soto - (K-08) - Roman Catholic

### Postsecondary

Jefferson College - Hillsboro: A public, two-year community college

### Public libraries

* Crystal City Public Library
* De Soto Public Library
* Festus Public Library
* Herculaneum Public Library
* Jefferson County Public Library

## Politics
### Local

Historically, the Democratic Party has controlled politics at the local level; starting in 2010 the Republican Party has flipped the county with 66% of the population voting Republican in 2020.

### State

Jefferson County is divided into seven legislative districts in the Missouri House of Representatives; all of which are held by Republicans. Jefferson County consists of two State Senate Districts.
Missouri House of Representatives — District 97 — Jefferson County (2020) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Mary Elizabeth Coleman | 13,260 | 100% | |
Missouri House of Representatives — District 97 — Jefferson County (2018) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Mary Elizabeth Coleman | 7,204 | 56.40% | |
| | Democratic | Mike Revis | 5,570 | 43.60% | |
Missouri House of Representatives — District 97 — Jefferson County (2016) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | John C. McCaherty | 10,386 | 74.00% | +7.02 |
| | Libertarian | Tracy J. Scott | 3,650 | 26.00% | +26.00 |
Missouri House of Representatives — District 97 — Jefferson County (2014) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | John C. McCaherty | 4,681 | 66.98% | +15.83 |
| | Democratic | Tom Dohack | 2,308 | 33.02% | −15.83 |
Past gubernatorial elections results :
| Year | Republican | Democratic | Third Parties |
| 2020 | 63.91% 73,942 | 33.59% 38,866 | 2.50% 2,886 |
| 2016 | 53.62% 56.755 | 42.74% 45.234 | 3.64% 3,848 |
| 2012 | 41.75% 40,470 | 55.68% 53,971 | 2.56% 2,484 |
| 2008 | 34.42% 35,947 | 63.87% 66,697 | 1.71% 1,781 |
| 2004 | 49.23% 45,891 | 49.25% 45,909 | 1.52% 1,424 |
| 2000 | 47.05% 36,060 | 49.33% 37,808 | 3.62% 2,775 |
| 1996 | 43.90% 28,986 | 52.96% 34,970 | 3.14% 2,077 |
Missouri House of Representatives — District 97 — Jefferson County (2012) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | John C. McCaherty | 6,946 | 51.15% | |
| | Democratic | Sam Komo | 6,633 | 48.85% | |
* District 111 Shane Roden (R-Cedar Hill). Consists of Byrnes Mill, Cedar Hill, Cedar Hill Lakes, House Springs, and Scottsdale.
Missouri House of Representatives — District 111 — Jefferson County (2020) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Shane Roden | 13,308 | 70.87% | |
| | Democratic | Daniel (Vern) Cherry | 5,470 | 29.13% | |
Missouri House of Representatives — District 111 — Jefferson County (2018) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Shane Roden | 9,826 | 65.34% | |
| | Democratic | Phoebe Ottomeyer | 5,212 | 34.66% | |
Missouri House of Representatives — District 111 — Jefferson County (2016) :
| Party | Candidate | Votes | % | ±% |
| Republican | Shane Roden | 10,699 | 62.10% | +9.12 |
| Democratic | Del Viehland | 5,020 | 29.14% | −17.88 |
| Independent | Jon Schuesller | 1,510 | 8.76% | +8.76 |
Missouri House of Representatives — District 111 — Jefferson County (2014) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Shane Roden | 4,834 | 52.98% | +3.66 |
| | Democratic | Michael Frame | 4,291 | 47.02% | −3.66 |
Missouri House of Representatives — District 111 — Jefferson County (2012) :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | Michael Frame | 8,052 | 50.68% | |
| | Republican | Derrick Good | 7,836 | 49.32% | |
* District 112 Rob Vescovo (R-Arnold). Consists of areas near Arnold and Byrnes Mill.
Missouri House of Representatives — District 112 — Jefferson County (2020) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Rob Vescovo | 16,545 | 100% | |
Missouri House of Representatives — District 112 — Jefferson County (2018) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Rob Vescovo | 16,545 | 61.30% | |
| | Democratic | Benjamin Hagin | 6,074 | 38.70% | |
Missouri House of Representatives — District 112 — Jefferson County (2016) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Rob Vescovo | 10,754 | 59.64% | −0.43 |
| | Democratic | Robert Butler | 7,278 | 40.36% | +0.43 |
Missouri House of Representatives — District 112 — Jefferson County (2014) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Rob Vescovo | 5,432 | 60.07% | +0.97 |
| | Democratic | Robert Butler | 3,611 | 39.93% | −0.97 |
Missouri House of Representatives — District 112 — Jefferson County (2012) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Paul Wieland | 9,284 | 59.10% | |
| | Democratic | Daniel James | 6,425 | 40.90% | |
* District 113 Dan Shaul (R-Imperial). Consists of most Arnold, all of Imperial and Kimmswick, and part of Barnhart.
Missouri House of Representatives — District 113 — Jefferson County (2020) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Dan Shaul | 11,150 | 63.19% | |
| | Democratic | Terry Burgess | 6,519 | 36.90% | |
Missouri House of Representatives — District 113 — Jefferson County (2018) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Dan Shaul | 7,940 | 56.52% | |
| | Democratic | Karen Settlemoir-Berg | 6,109 | 43.48% | |
Missouri House of Representatives — District 113 — Jefferson County (2016) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Dan Shaul | 9,598 | 57.84% | −2.14 |
| | Democratic | Karen Settlemoir-Berg | 6,995 | 42.16% | +2.14 |
Missouri House of Representatives — District 113 — Jefferson County (2014) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Dan Shaul | 4,749 | 59.98% | +13.21 |
| | Democratic | Sean Fauss | 3,168 | 40.02% | −13.21 |
Missouri House of Representatives — District 113 — Jefferson County (2012) :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | Jeff Roorda | 8,450 | 53.23% | |
| | Republican | Dan Smith | 7,225 | 46.77% | |
* District 114 Becky Ruth (R-Festus). Consists of part of Barnhart, and all of Crystal City, Festus, Herculaneum, and Pevely.
Missouri House of Representatives — District 114 — Jefferson County (2020) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Becky Ruth | 15,798 | 100.00% | |
Missouri House of Representatives — District 114 — Jefferson County (2018) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Becky Ruth | 9,664 | 67.64% | |
| | Democratic | Dennis McDonald | 4,624 | 32.36% | |
Missouri House of Representatives — District 114 — Jefferson County (2016) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Becky Ruth | 14,639 | 100.00% | +46.74% |
Missouri House of Representatives — District 114 — Jefferson County (2014) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Becky Ruth | 4,791 | 53.26% | +3.53 |
| | Democratic | T. J. McKenna | 4,204 | 46.74% | −3.53 |
Missouri House of Representatives — District 114 — Jefferson County (2012) :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | T. J. McKenna | 7,772 | 50.27% | |
| | Republican | Becky Ruth | 7,688 | 49.73% | |
* District 115 Cyndi Buchheit-Courtway (R-Festus). Consists of Olympian Village and areas near De Soto.
Missouri House of Representatives — District 115 — Jefferson County (2020) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Cyndi Buchheit Courtway | 6,444 | 69.32% | +5.68 |
| | Democratic | Cynthia Nugent | 2,835 | 27.97% | |
Missouri House of Representatives — District 115 — Jefferson County (2018) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Elaine Freeman Gannon | 6,671 | 100% | |
Missouri House of Representatives — District 115 — Jefferson County (2016) :
| Party | Candidate | Votes | % | ±% |
| Republican | Elaine Gannon | 6,444 | 69.32% | +5.68 |
| Democratic | Barbara Stocker | 2,443 | 26.28% | −5.12 |
| Libertarian | Charles Bigelow | 409 | 4.40% | +4.40 |
Missouri House of Representatives — District 115 — Jefferson County (2014) :
| Party | Candidate | Votes | % | ±% |
| Republican | Elaine Gannon | 3,285 | 63.64% | +12.75 |
| Democratic | Dan Darian | 1,621 | 31.40% | −17.71 |
| Constitution | Jerry Dollar, Jr. | 256 | 4.96% | +4.96 |
Missouri House of Representatives — District 115 — Jefferson County (2012) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Elaine Gannon | 4,329 | 50.89% | |
| | Democratic | Rich McCane | 4,177 | 49.11% | |
* District 118 Mike McGirl (R-Potosi). Consists of De Soto and Hillsboro.
Missouri House of Representatives — District 118 — Jefferson County (2020) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Mike McGirl | 9,259 | 100.00% | |
Missouri House of Representatives — District 118 — Jefferson County (2018) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Mike McGirl | 5,336 | 62.19% | |
| | Democratic | Barbara Marco | 3,244 | 37.81% | |
Missouri House of Representatives — District 118 — Jefferson County (2016) :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | Ben Harris | 8,164 | 100.00% | +44.57 |
Missouri House of Representatives — District 118 — Jefferson County (2014) :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | Ben Harris | 3,239 | 55.43% | −44.57 |
| | Republican | Michael McGirl | 2,604 | 44.57% | +44.57 |
Missouri House of Representatives — District 118 — Jefferson County (2012) :
| Party | Party | Candidate | Votes | % | ±% |
| | Democratic | Ben Harris | 7,514 | 100.00% | |
Jefferson County is also divided into two districts in the Missouri Senate.
* District 3 — Elaine Gannon (R-De Soto) Consists of De Soto, Hillsboro, and Olympian Village as well as part of Festus.
Missouri Senate — District 3 — Jefferson County (2020) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Elaine Freeman Gannon | 20,578 | 100% | |
| | Green | Edward Weissler | 4,681 | 22.24% | +22.24 |
Missouri Senate — District 3 — Jefferson County (2016) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Gary Romine | 16,356 | 77.75% | +27.90 |
| | Green | Edward Weissler | 4,681 | 22.24% | +22.24 |
Missouri Senate — District 3 — Jefferson County (2012) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Gary Romine | 10,069 | 49.85 | |
| | Democratic | Joseph Fallert, Jr. | 10,129 | 50.15 | |
* District 22 — Paul Wieland (R-Imperial) Consists of the northern part of the county.
Missouri Senate — District 22 — Jefferson County (2018) :
| Party | Candidate | Votes | % |
| Republican | Paul Wieland | 40,556 | 58.32 |
| Democratic | Robert Butler | 26.903 | 38.69 |
| Libertarian | Richie Camden | 2,078 | 2.99 |
Missouri Senate — District 22 — Jefferson County (2014) :
| Party | Party | Candidate | Votes | % | ±% |
| | Republican | Paul Wieland | 22,208 | 54.19 | |
| | Democratic | Jeff Roorda | 18,774 | 45.81 | |

### Federal

U.S. Senate — Missouri — (2018) :
| Party | Candidate | Votes | % |
| Republican | Josh Hawley | 49,142 | 54.33% |
| Democratic | Claire McCaskill | 37,915 | 41.92% |
| Independent | Craig O'Dear | 1,550 | 1.71% |
| Libertarian | Japheth Campbell | 1,207 | 1.33% |
| Green | Jo Crain | 633 | 0.70% |
U.S. Senate — Missouri — (2016) :
| Party | Candidate | Votes | % | ±% |
| Republican | Roy Blunt | 53,218 | 50.34% | +10.37 |
| Democratic | Jason Kander | 46,975 | 44.44% | −9.07 |
| Libertarian | Jonathan Dine | 2,941 | 2.78% | −3.74 |
| Green | Johnathan McFarland | 1,450 | 1.37% | +1.37 |
| Constitution | Fred Ryman | 1,124 | 1.06% | +1.06 |
U.S. Senate — Missouri — (2012) :
| Party | Candidate | Votes | % |
| Democratic | Claire McCaskill | 51,862 | 53.51% |
| Republican | Todd Akin | 38,745 | 39.97% |
| Libertarian | Jonathan Dine | 6,316 | 6.52% |
Jefferson County is divided among three congressional districts. Prior to the 2012 election all of it was included in Missouri's 3rd Congressional District, but now about half of it is in the 3rd District, while the northeastern portion is in the 2nd Congressional District and the southern portion is in the 8th Congressional District.
U.S. House of Representatives — District 2 — Jefferson County (2016) :
| Party | Candidate | Votes | % | ±% |
| Republican | Ann Wagner | 11,930 | 61.04% | −0.87 |
| Democratic | Bill Otto | 6,542 | 33.47% | −0.10 |
| Libertarian | Jim Higgins | 783 | 4.00% | −0.52 |
| Green | David Justus Arnold | 291 | 1.49% | +1.49 |
U.S. House of Representatives — District 2 — Jefferson County (2014) :
| Party | Candidate | Votes | % | ±% |
| Republican | Ann Wagner | 5,988 | 61.91% | +6.38 |
| Democratic | Arthur Lieber | 3,247 | 33.57% | −7.41 |
| Libertarian | Bill Slantz | 437 | 4.52% | +1.68 |
U.S. House of Representatives — District 2 — Jefferson County (2012) :
| Party | Candidate | Votes | % |
| Republican | Ann Wagner | 9,976 | 55.53% |
| Democratic | Glenn Koenen | 7,361 | 40.98% |
| Libertarian | Bill Slantz | 511 | 2.84% |
| Constitution | Anatol Zorikova | 116 | 0.65% |
U.S. House of Representatives — District 3 — Jefferson County (2016) :
| Party | Candidate | Votes | % | ±% |
| Republican | Blaine Luetkemeyer | 33,530 | 61.56% | +1.44 |
| Democratic | Kevin Miller | 18,333 | 33.66% | −1.33 |
| Libertarian | Dan Hogan | 2,077 | 3.81% | −1.07 |
| Constitution | Doanita Simmons | 526 | 0.97% | +0.97 |
U.S. House of Representatives — District 3 — Jefferson County (2014) :
| Party | Candidate | Votes | % | ±% |
| Republican | Blaine Luetkemeyer | 16,558 | 60.12% | +7.09 |
| Democratic | Courtney Denton | 9,637 | 34.99% | −7.29 |
| Libertarian | Steven Hedrick | 1,345 | 4.88% | +0.19 |
U.S. House of Representatives — District 3 — Jefferson County (2012) :
| Party | Candidate | Votes | % |
| Republican | Blaine Luetkemeyer | 25,898 | 53.03% |
| Democratic | Eric Mayer | 20,650 | 42.28% |
| Libertarian | Steven Wilson | 2,288 | 4.69% |
U.S. House of Representatives — District 8 — Jefferson County (2016) :
| Party | Candidate | Votes | % | ±% |
| Republican | Jason Smith | 18,030 | 63.98% | +11.75 |
| Democratic | Dave Cowell | 9,155 | 32.49% | −5.26 |
| Libertarian | Jonathan Shell | 996 | 3.53% | +0.70 |
U.S. House of Representatives — District 8 — Jefferson County (2014) :
| Party | Candidate | Votes | % | ±% |
| Republican | Jason Smith | 8,060 | 52.23% | −5.47 |
| Democratic | Barbara Stocker | 5,826 | 37.75% | −0.80 |
| Libertarian | Rick Vandeven | 436 | 2.83% | +1.22 |
| Constitution | Doug Enyart | 544 | 3.52% | +1.38 |
| Independent | Terry Hampton | 567 | 3.67% | |
U.S. House of Representatives — District 8 — Jefferson County (Special Election, June 4, 2013) :
| Party | Candidate | Votes | % | ±% |
| Republican | Jason Smith | 1,862 | 57.70% | +0.78 |
| Democratic | Steve Hodges | 1,244 | 38.55% | −0.54 |
| Libertarian | Bill Slantz | 52 | 1.61% | −2.38 |
| Constitution | Doug Enyart | 69 | 2.14% | +2.14 |
U.S. House of Representatives — District 8 — Jefferson County (2012) :
| Party | Candidate | Votes | % |
| Republican | Joann Emerson | 14,692% | 56.92 |
| Democratic | Jack Rushin | 10,090 | 39.09% |
| Libertarian | Rick Vandeven | 1,030 | 3.99% |

#### Political culture

United States presidential election results for Jefferson County, Missouri :
| Year | Republican | Republican | Democratic | Democratic | Third party(ies) | Third party(ies) |
| Year | No. | % | No. | % | No. | % |
| 2024 | 80,796 | 67.42% | 36,965 | 30.85% | 2,072 | 1.73% |
| 2020 | 77,046 | 65.88% | 37,523 | 32.08% | 2,384 | 2.04% |
| 2016 | 69,036 | 64.52% | 31,568 | 29.50% | 6,391 | 5.97% |
| 2012 | 53,978 | 55.07% | 41,564 | 42.40% | 2,482 | 2.53% |
| 2008 | 50,804 | 47.91% | 53,467 | 50.42% | 1,779 | 1.68% |
| 2004 | 46,624 | 49.99% | 46,057 | 49.38% | 583 | 0.63% |
| 2000 | 36,766 | 47.62% | 38,616 | 50.02% | 1,822 | 2.36% |
| 1996 | 23,877 | 36.12% | 32,073 | 48.52% | 10,152 | 15.36% |
| 1992 | 20,637 | 28.08% | 32,569 | 44.31% | 20,295 | 27.61% |
| 1988 | 29,279 | 51.16% | 27,738 | 48.47% | 215 | 0.38% |
| 1984 | 34,525 | 63.29% | 20,026 | 36.71% | 0 | 0.00% |
| 1980 | 28,546 | 52.01% | 24,042 | 43.81% | 2,294 | 4.18% |
| 1976 | 18,261 | 41.58% | 25,159 | 57.29% | 495 | 1.13% |
| 1972 | 21,947 | 61.42% | 13,787 | 38.58% | 0 | 0.00% |
| 1968 | 11,708 | 37.70% | 13,230 | 42.60% | 6,115 | 19.69% |
| 1964 | 7,887 | 29.43% | 18,916 | 70.57% | 0 | 0.00% |
| 1960 | 12,910 | 43.09% | 17,054 | 56.91% | 0 | 0.00% |
| 1956 | 10,712 | 43.58% | 13,868 | 56.42% | 0 | 0.00% |
| 1952 | 9,607 | 42.82% | 12,808 | 57.08% | 22 | 0.10% |
| 1948 | 6,085 | 37.02% | 10,280 | 62.55% | 70 | 0.43% |
| 1944 | 6,758 | 45.83% | 7,953 | 53.94% | 34 | 0.23% |
| 1940 | 7,517 | 43.92% | 9,553 | 55.82% | 45 | 0.26% |
| 1936 | 5,575 | 37.23% | 9,158 | 61.16% | 241 | 1.61% |
| 1932 | 4,559 | 35.50% | 8,130 | 63.30% | 155 | 1.21% |
| 1928 | 6,285 | 54.47% | 5,231 | 45.34% | 22 | 0.19% |
| 1924 | 4,870 | 48.88% | 4,356 | 43.72% | 737 | 7.40% |
| 1920 | 5,730 | 54.08% | 4,684 | 44.21% | 181 | 1.71% |
| 1916 | 3,310 | 51.01% | 3,021 | 46.56% | 158 | 2.43% |
| 1912 | 2,127 | 40.84% | 2,368 | 45.47% | 713 | 13.69% |
| 1908 | 3,050 | 52.00% | 2,698 | 46.00% | 117 | 1.99% |
| 1904 | 2,909 | 52.09% | 2,560 | 45.84% | 116 | 2.08% |
| 1900 | 2,775 | 49.20% | 2,798 | 49.61% | 67 | 1.19% |
| 1896 | 2,876 | 50.46% | 2,785 | 48.87% | 38 | 0.67% |
| 1892 | 2,207 | 44.70% | 2,617 | 53.01% | 113 | 2.29% |
| 1888 | 2,228 | 47.31% | 2,438 | 51.77% | 43 | 0.91% |
A predominantly suburban county, Jefferson County used to be fairly independent-leaning at the federal level with a tendency to tilt Democratic. Presidential elections in Jefferson County were often very close; George W. Bush just narrowly carried the county in 2004 by less than 600 votes and by just over a half of a percentage point. Al Gore and Barack Obama also just narrowly carried the county in 2000 and 2008, respectively. Bill Clinton, however, did manage to carry Jefferson County by double digits both times in 1992 and 1996. However, in 2012 the county, in line with the state as a whole, began to swing hard to the right with Mitt Romney carrying it with 55% of the vote. In 2016 Donald Trump won the county with 65% of the vote, the largest margin of any candidate since Lyndon Johnson in 1964.
Typical of the suburban culture in most counties throughout the country, voters in Jefferson County tend to be rather centrist on social issues but more liberal on economic issues. In 2004, Missourians voted on a constitutional amendment to define marriage as the union between a man and a woman—it overwhelmingly passed Jefferson County with 72.56 percent of the vote. The initiative passed the state with 71 percent of support from voters as Missouri became the first state to ban same-sex marriage. In 2006, Missourians voted on a constitutional amendment to fund and legalize embryonic stem cell research in the state—it narrowly passed Jefferson County with 51.85 percent voting for the measure. The initiative narrowly passed the state with 51 percent of support from voters as Missouri became one of the first states in the nation to approve embryonic stem cell research. In 2006, Missourians voted on a proposition (Proposition B) to increase the minimum wage in the state to $6.50 an hour—it passed Jefferson County with 79.90 percent of the vote. The proposition strongly passed every single county in Missouri with 78.99 percent voting in favor as the minimum wage was increased to $6.50 an hour in the state. During the same election, voters in five other states also strongly approved increases in the minimum wage.

#### 2008 Missouri presidential primary
##### Republican

U.S. Senator John McCain (R-Arizona) won Jefferson County with 33.54% of the vote. Former Governor Mitt Romney (R-Massachusetts finished in second with 30.45% of the vote, while former Governor Mike Huckabee (R-Arkansas) came in third with 30.19% in Jefferson County. Libertarian-leaning U.S. Representative Ron Paul (R-Texas) finished a distant fourth place with 3.94% of the vote in Jefferson County. McCain received all of Missouri's 58 delegates as the Republican Party utilizes the winner-takes-all system.

##### Democratic

U.S. Senator Hillary Clinton (D-New York) won Jefferson County over Senator Barack Obama (D-Illinois) with 61.32% of the vote, while Obama received 35.02% of the vote. Although he withdrew from the race, former U.S. Senator John Edwards (D-North Carolina) still received 2.74% of the vote in Jefferson County. Jefferson County gave Clinton one of her strongest showings in a predominantly suburban county in the entire country.
Clinton had a large initial lead in Missouri at the beginning of the evening as the rural precincts began to report, leading several news organizations to call the state for her; however, Obama rallied from behind as the heavily African American precincts from St. Louis began to report and eventually put him over the top. In the end, Obama received 49.32 percent of the vote to Clinton's 47.90% — a 1.42% difference. Both candidates split Missouri's 72 delegates, as the Democratic Party utilizes proportional representation.
Hillary Rodham Clinton received more votes, a total of 19,075, than any candidate from either party in Jefferson County during the 2008 Missouri Presidential Primaries. She also received more votes than the total number of votes cast in the entire Republican Primary in Jefferson County.

## Health

According to a 2012 census study by the University of Wisconsin Population Health Institute and the Robert Wood Johnson Foundation, Jefferson County led the Saint Louis metropolitan area in the number of adults who smoke, roughly 30% of all adult residents of Jefferson County smoked or used tobacco in some form, compared to the 19% national average and the 24% Missouri state average.
Jefferson County and the state of Missouri led the nation in methamphetamine production, peaking in the mid-2000s.

## Jefferson County Parks and Recreation

* Big River Saddle Club
* Brown's Ford
* Cedar Hill
* Fletcher House
* High Ridge Civic Center
* Rockford Beach
* Jefferson Winter Park
* Morse Mill
* Pleasant Valley
* Sunridge
* NW Jefferson County Sports Complex

## Communities
### Cities

* Arnold
* Byrnes Mill
* Crystal City
* De Soto
* Festus
* Herculaneum
* Hillsboro (county seat)
* Kimmswick
* Olympian Village
* Pevely

### Villages

* Cedar Hill Lakes
* Lake Tekakwitha
* Parkdale
* Peaceful Village
* Scotsdale

### Townships

* Big River
* Central
* High Ridge
* Joachim
* Meramec
* Plattin
* Rock
* Valle

### Census-designated places

* Barnhart
* Briarwood Estates
* Cedar Hill
* High Ridge
* Horine
* Imperial
* LaBarque Creek
* Murphy
* Raintree Plantation
* Summer Set

### Other unincorporated communities

* Antonia
* Bailey
* Belews Creek
* Bushburg
* Byrnesville
* Danby
* Dittmer
* Donnell
* Fletcher
* Flucom
* Frumet
* Goldman
* Grubville
* Hematite
* House Springs
* Jarvis
* Knorpp
* Liguori
* Local
* Ludwig
* Mapaville
* Melzo
* Meramec Heights
* Morse Mill
* Munsons
* Oermann
* Old Mines
* Papin
* Plattin
* Regina
* Riverside
* Rush Tower
* Seckman
* Selma
* Sulphur Springs
* Valles Mines
* Victoria
* Vineland
* Ware