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Mason County

Washington·FIPS 53045·71,165 residents (2025 estimate)

2024 result

R+2.5

36,689 ballots cast

What happened: the county's margin each cycle, against the national result.

D+12D+6EvenR+6R+122000200420082012201620202024D+2.8D+3.6D+8.7D+7.1R+6R+3.9R+2.5
This countyNational margin

Lean vs. nation

R+1.1

How this county sits relative to the country in 2024, with the national environment removed.

Trend since 2000

-3.4 pts

Net movement of that lean across 7 cycles — toward Republicans.

Elasticity

0.52

Moves roughly in step with the country.

Bellwether error

4.5

Average gap between this county's margin and the nation's.

Flipped 1 time since 2000 — 2016 to R

Votes by candidate

7 cycles

Certified vote counts for each party's nominee, the combined total for everyone else on the ballot, the number of ballots cast, and how many people lived here at the time.

2024

R+2.5margin
Donald TrumpRep
18,127
49.4%
Kamala HarrisDem
17,215
46.9%
All other candidates
1,347
3.7%

36,689 ballots cast · 52.6 per 100 residents (2024 population estimate)

Residents69,759+5.6% since 2020 (+3,718 people)

2020

R+3.9margin
Donald TrumpRep
18,710
50.2%
Joe BidenDem
17,269
46.3%
All other candidates
1,324
3.5%

37,303 ballots cast · 56.5 per 100 residents (2020 population estimate)

Residents66,041+6.3% since 2016 (+3,899 people)

Measured across a change of Census vintage. The two series share no common year, so how far apart they sit cannot be measured — this change carries an unknown amount of revision on top of four years of real change.

2016

R+6.0margin
Donald TrumpRep
13,677
48.7%
Hillary ClintonDem
11,993
42.7%
All other candidates
2,403
8.6%

28,073 ballots cast · 45.2 per 100 residents (2016 population estimate)

Residents62,142+2.4% since 2012 (+1,461 people)

2012

D+7.1margin
Barack ObamaDem
14,764
52.3%
Mitt RomneyRep
12,761
45.2%
All other candidates
710
2.5%

28,235 ballots cast · 46.5 per 100 residents (2012 population estimate)

Residents60,681+1.5% since 2008 (+896 people)

Measured across a change of Census vintage. Where the two vintages overlap, 96% of counties agree within 0.5%, so read this figure to about half a point and no finer.

2008

D+8.7margin
Barack ObamaDem
15,050
53.2%
John McCainRep
12,600
44.5%
All other candidates
656
2.3%

28,306 ballots cast · 47.3 per 100 residents (2008 population estimate)

Residents59,785+11.1% since 2004 (+5,966 people)

2004

D+3.6margin
John KerryDem
12,894
50.8%
George W. BushRep
11,987
47.2%
All other candidates
513
2.0%

25,394 ballots cast · 47.2 per 100 residents (2004 population estimate)

Residents53,819+8.4% since 2000 (+4,188 people)

2000

D+2.8margin
Al GoreDem
10,876
48.4%
George W. BushRep
10,257
45.6%
All other candidates
1,346
6.0%

22,479 ballots cast · 45.3 per 100 residents (2000 population estimate)

Residents49,631

“All other candidates” is every remaining line on the presidential ballot combined — minor parties, independents and write-ins where the state reports them. Shares are of all ballots cast, so the three rows sum to 100%.

Ballots cast per 100 residents is not a turnout rate. It measures votes against every resident — children and non-citizens included — not against eligible or registered voters, which is what turnout means and which this site does not have a county-level figure for. It is shown only where an election year and a population estimate share the same year and describe the same territory; where the Census figure is stated on boundaries the vote was not cast on, the card says so and the ratio is withheld.

A change in residents is not a change in voters. The percentage beside each year is the change in resident population since the previous presidential election — everyone who lives here, including children and non-citizens. It is not turnout, not registration, and not the same quantity as the change in ballots cast. Population is measured on 1 July of the election year, four months before the vote, which is the closest an annual series gets to election day.

Population figures on this page come from 3 Census series: PEP intercensal county estimates, 2000–2010; PEP vintage 2019 county estimates, 2010–2019; PEP vintage 2025 county estimates, 2020–2025. The 2012 and 2020 figures are the first in a new series, so the change shown for those years is measured across a change of Census method as well as across four years. Each of those cards says so. Two figures drawn from different vintages are not two readings of one series.

Every cycle

YearMarginLeanSwingRel. swingVotes3rd party
2024R+2.5R+1.1+1.4+7.536,6893.7%
2020R+3.9R+8.5+2.5+0.337,3033.5%
2016R+6.0R+8.8-13.8-12.028,0738.6%
2012D+7.1D+3.3-1.6+1.828,2352.5%
2008D+8.7D+1.5+5.2-4.628,3062.3%
2004D+3.6D+6.1+0.7+3.825,3942.0%
2000D+2.8D+2.322,4796.0%

Margin is over all votes cast. Lean is the two-party margin minus the nation's — the county's own position with the national environment removed. Relative swing is the change in that lean. “Votes” is the number of ballots cast in the presidential contest, not a share of eligible voters.

Counties on a similar trajectory

Sources

Presidential returns from the MIT Election Data and Science Lab (County Presidential Returns 2000–2024, CC0). Geography and FIPS codes from the US Census Bureau (public domain). Where a state reports both a total and per-mode vote counts, the reported total is used.

Resident population from the US Census Bureau, Population Estimates Program (Vintage 2025), measured as of July 1, 2025. Resident population — all residents, including children and non-citizens. Not an electorate, and not comparable to a vote total as a turnout rate. Conclusions drawn from it are ours, not the Bureau's.

Population at each election is measured on 1 July of the election year and comes from the US Census Bureau's Population Estimates Program (public domain). The 2000–2024 span is covered by several separately estimated vintages of that programme rather than by one continuous series — the ones used on this page are named under the cycle cards, and every change measured across a boundary between them is marked there. Notes about territory changing hands come from this site's own change ledger and are only as complete as it is.