Massachusetts Cape and Islands District

State Legislative District Profile (Upper Chamber)

Overview

District ID
ma-sd-d40
State
Massachusetts
Chamber
Upper chamber (state senate)
District Code
D40
Land Area
392.6 sq mi
Water Area
1,498.4 sq mi

Boundary

Boundary of Massachusetts Cape and Islands District

Boundary as GeoJSON

Source: U.S. Census Bureau TIGER/Line state legislative district boundaries.

Counties

CountyOverlapShare of district landShare of county land
Barnstable County243.22 sq mi61.9%61.7%
Dukes County103.20 sq mi26.3%100.0%
Nantucket County46.19 sq mi11.8%100.0%

Showing all 3 counties

Places

PlaceOverlapShare of district landShare of place land
Barnstable Town city59.93 sq mi15.3%100.0%
East Harwich CDP8.02 sq mi2.0%100.0%
Northwest Harwich CDP7.98 sq mi2.0%100.0%
South Yarmouth CDP6.96 sq mi1.8%100.0%
West Yarmouth CDP6.69 sq mi1.7%100.0%
Yarmouth Port CDP6.02 sq mi1.5%100.0%
Nantucket CDP5.82 sq mi1.5%100.0%
Dennis CDP4.91 sq mi1.3%100.0%
East Dennis CDP4.83 sq mi1.2%100.0%
South Dennis CDP4.55 sq mi1.2%100.0%
Brewster CDP3.90 sq mi1.0%100.0%
North Eastham CDP3.44 sq mi0.9%100.0%
West Dennis CDP3.26 sq mi0.8%100.0%
Dennis Port CDP3.04 sq mi0.8%100.0%
West Chatham CDP2.92 sq mi0.7%100.0%
Chatham CDP2.64 sq mi0.7%100.0%
Harwich Port CDP2.63 sq mi0.7%100.0%
Orleans CDP2.32 sq mi0.6%100.0%
Harwich Center CDP2.25 sq mi0.6%100.0%
Siasconset CDP2.13 sq mi0.5%100.0%
Madaket CDP1.99 sq mi0.5%100.0%
Oak Bluffs CDP1.81 sq mi0.5%100.0%
Provincetown CDP1.79 sq mi0.5%100.0%
Vineyard Haven CDP1.30 sq mi0.3%100.0%
Edgartown CDP1.20 sq mi0.3%100.0%

Showing all 25 places

Overlapping Congressional Districts

Congressional districtPopulation in bothShare of this district's populationShare of the congressional district's populationShare of this district's land
MA District 9175,563100.0%22.5%100.0%

Source: U.S. Census Bureau 2020 blocks and 2025 block equivalency files (119th Congress, 2024 state legislative plans).

Voters

Registered Voters
148,591
Active Voters
126,805 (85.3%)

Party Registration

PartyVotersShare
Democratic34,55623.3%
Republican<10—
Unaffiliated00.0%
Other parties98,27166.1%
No party recorded<10—

Turnout by Cycle

CycleGeneralDemocratic PrimaryRepublican Primary
2025–202624,589 (16.5%)0 (0.0%)0 (0.0%)
2023–2024109,475 (73.7%)29,561 (19.9%)23,607 (15.9%)
2021–202285,867 (57.8%)26,297 (17.7%)13,288 (8.9%)
2019–2020102,975 (69.3%)50,974 (34.3%)15,820 (10.6%)
2017–201882,286 (55.4%)18,185 (12.2%)10,920 (7.3%)
2015–201687,958 (59.2%)33,341 (22.4%)20,210 (13.6%)
2013–201462,985 (42.4%)13,402 (9.0%)6,632 (4.5%)
2011–201277,791 (52.4%)11,828 (8.0%)12,992 (8.7%)

Turnout counts today's registered voters with a counted ballot in the cycle's elections (the odd and even year), as a share of today's registered voters. Voters who have since left the rolls are not counted.

Browse the voter list for this district (premium access; sign-in required)

Source: Civitech voter file snapshot as of 12/07/2025. These are registered voters, separate from the Census population figures. Counts under 10 are suppressed and shown as "<10".

Demographics

Total Population
177,816 (± 36)
Median Age
54.1
Median Household Income
$96,774 (± $2,682)
High School Graduate or Higher (age 25+)
95.7%
Bachelor's Degree or Higher (age 25+)
48.8%

Population by Age

GroupPeopleShare
Under 1825,66414.4%
18 to 6495,51853.7%
65 and over56,63431.8%

Population by Race and Hispanic Origin

GroupPeopleShare
Hispanic or Latino (any race)8,8205.0%
White, not Hispanic144,91181.5%
Black, not Hispanic7,4444.2%
Asian, not Hispanic2,4041.4%
American Indian / Alaska Native, not Hispanic3790.2%
Native Hawaiian / Pacific Islander, not Hispanic00.0%
Some other race, not Hispanic3,3191.9%
Two or more races, not Hispanic10,5395.9%

Source: U.S. Census Bureau, American Community Survey 2020-2024 ACS 5-year estimates (tables B01001, B01002, B01003, B03002, B15003, B19013) for this state legislative district. Estimates are survey-based; ± figures are 90% margins of error.

Citizen Voting Age Population

Total Citizen Population
167,516
Citizen Voting Age Population (CVAP)
143,039

Citizen Population by Race/Ethnicity

GroupCitizensShare
Non-Hispanic160,74596.0%
Hispanic6,7674.0%
White148,63888.7%
Black5,7783.4%
Asian1,9441.2%
American Indian / Alaska Native3650.2%
Native Hawaiian / Pacific Islander250.0%
Two or More Races3860.2%

Citizen Voting Age Population by Race/Ethnicity

GroupCVAPShare
Non-Hispanic138,50596.8%
Hispanic4,5373.2%
White130,06990.9%
Black5,3043.7%
Asian1,8431.3%
American Indian / Alaska Native1,1450.8%
Native Hawaiian / Pacific Islander250.0%
Two or More Races3070.2%

Source: Redistricting Data Hub / U.S. Census Bureau CVAP Special Tabulation (2020-2024 ACS 5-year).