Question 1

How did Jefferson, Iowa vote in the 2024 presidential election?

Accepted Answer

Jefferson, Iowa voted Republican in 2024 with a margin of R+6.8. Kamala D Harris received 3,788 votes and Donald Trump received 4,353 out of 8,346 total votes cast, a 5.4-point shift toward Republicans from 2020.

Question 2

What is Jefferson, Iowa's political history?

Accepted Answer

Jefferson, Iowa has 40 presidential elections on record, spanning 1868 to 2024. Democrats have won 7 and Republicans 33 of those contests. The largest single-election swing was 54.7 points in 1932.

Question 3

What are the demographics of Jefferson, Iowa?

Accepted Answer

Jefferson, Iowa has a population of 15,705 according to the 2020 Census. The racial composition is 82.4% non-Hispanic white, 4.1% Hispanic, 2.5% Black. About 43% of residents hold a bachelor's degree or higher. Median household income is $61,620.

Question 4

Which places are most similar to Jefferson, Iowa?

Accepted Answer

Based on demographic and electoral similarity analysis, the three most similar countys to Jefferson, Iowa are Grafton, Franklin, Broome. Similarity is computed using a vector embedding of demographic, economic, and electoral characteristics.

Group	%
▶White (Non-Hispanic)(13)	82.4%
▶Hispanic / Latino(5)	4.1%
▶Black / African American(5)	2.5%
▶Asian(4)	8.2%
▶Middle Eastern / North African(4)	1.6%
▶Native American / Alaska Native(1)	0.8%
Multiracial / Other	2.0%

Tradition	% Pop	% Adherents
Mainline Protestant	11.6%	38.6%
Catholic	6.4%	21.5%
Other	6.0%	20.1%
Evangelical Protestant	5.9%	19.8%
LDS (Mormon)	2.1%	7.1%
Non-religious	70.0%	—

Year	Result
2024	Trump+6.8
2020	Trump+1.4
2016	Trump+0.5
2012	Obama+16.0
2008	Obama+20.2
2004	Kerry+10.2
2000	Bush+5.1
1996	Clinton+0.8
1992	Clinton+0.3

Year	Dem %	Rep %	Margin	Swing
2024	45.4%	52.2%	R+6.8	R+5.4
2020	48.2%	49.6%	R+1.4	R+0.9
2016	44.8%	45.2%	R+0.5	R+16.4
2012	56.2%	40.3%	D+16.0	R+4.3
2008	58.7%	38.5%	D+20.2	D+10.1
2004	54.2%	44.1%	D+10.2	D+15.3
2000	37.9%	43.0%	R+5.1	R+5.9
1996	35.1%	34.4%	D+0.8	D+0.5
1992	30.7%	30.5%	D+0.3	D+0.5
1988	49.3%	49.5%	R+0.3	D+22.6
1984	38.3%	61.2%	R+22.9	R+2.0
1980	35.3%	56.2%	R+20.9	R+15.8
1976	46.6%	51.7%	R+5.1	D+26.6
1972	33.1%	64.8%	R+31.7	R+7.0
1968	34.7%	59.5%	R+24.8	R+44.7
1964	59.8%	39.8%	D+19.9	D+48.0
1960	36.0%	64.0%	R+28.0	R+2.4
1956	37.1%	62.8%	R+25.6	D+13.2
1952	30.3%	69.1%	R+38.8	R+26.5
1948	42.8%	55.1%	R+12.3	—

Jefferson County, Iowa

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