County Treasurer, Plymouth County
Plymouth County, Massachusetts
My vote power
Below average
Election date
September 1, 2026 · Primary election
How do we calculate my vote power?
What goes into the rating: Representation: how much weight one vote carries here compared with a statewide vote — the smaller the district, the more each vote counts. Decisiveness: how likely this race is to be close, based on past results or current analyst ratings, plus the number of candidates.
Representation: Above average · 61 out of 100
This district is a good deal smaller than its state, so each vote here carries more weight than a vote in a statewide race. About 535,075 people live here.
Show the representation math
score = 50 + 50 × ln(state population ÷ this district's) ÷ ln(50,000) = 50 + 50 × ln(7,044,056 ÷ 535,075) ÷ ln(50,000) = 61.91, measured against a statewide vote in MA (grades: 66+ high, 55+ above average, 33+ average, otherwise low; a statewide race is the 50 baseline)
Decisiveness: None · only 1 candidate
One candidate is running unopposed, so votes can't change the outcome.
Above average representation + an uncontested race → My vote power: Below average.
About this office
- Collecting property taxes, in many counties
- Investing county money until it is spent
- Paying the county's bills on time
Affects: Anti-Corruption, Government Efficiency, Government Spending Reduction,
Candidates
Thomas J. O'Brien
AdvancedDemocratic · Incumbent · advanced
Thomas J. O'Brien is the Democratic incumbent candidate for Plymouth County Treasurer. He has served as Plymouth County Treasurer since 2006.
Results
Advanced · Certified
Winner: Thomas J. O'Brien (Democratic)
Source: electionstats.state.ma.us · researched September 12, 2026
Advanced · Unofficial
Winner: Thomas J. O'Brien (Democratic)
Source: electionstats.state.ma.us · researched September 12, 2026
Sources: sec.state.ma.us23