99chambers

Massachusetts House of Representatives seat · lines in effect since 2022

Massachusetts House of Representatives: 15th Suffolk District

A district of about 40,000 people, 21% Hispanic, 70% of adults with a bachelor's degree. It votes D+83.4 relative to the nation for president.

Sam Montaño (D)Next election Nov 7, 2028The 2026 race →

Where it sits among all 160 seats

Every Massachusetts House of Representatives seat by partisan lean, from most Democratic to most Republican. Lean is the seat's presidential vote on current lines, relative to the nation.

D+83.42nd most
Democratic
Most DemocraticMost Republican81st seat · the majority lineDistrict 137

Source: 99chambers: 2024 and 2020 presidential results on current lines, relative to the nation (2024 weighted 3:1)Updated Oct 16, 2026, 5:19 AM ET

Every race on these lines

Results recomputed from precinct returns as if today's boundaries had always existed, so years compare like for like.

2024
U.S. SenateD+79.2

Outlined: the race for this seat itselfBlank: no race that year

Source: 99chambers results archive: precinct results allocated to current lines; 2026: civicAPIUpdated Nov 7, 2026, 3:01 PM ET

Who lives here, compared

Grey bars show the spread of all 160 seats. Small marks are other seats in Massachusetts. The black marker is District 137.

Adults with a bachelor's degree70% 86th pct · 23rd of 160 in MA

Higher than 86% of seats.

White adults without a degree9% 5th pct · 152nd of 160 in MA

Lower than 95% of seats.

Hispanic residents21% 84th pct · 26th of 160 in MA

Higher than 84% of seats.

Black residents12% 88th pct · 20th of 160 in MA

Higher than 88% of seats.

Asian residents8% 65th pct · 57th of 160 in MA

Higher than 65% of seats.

People per square mile14,042 91st pct · 16th of 160 in MA

Denser than 91% of seats.

Source: Census Bureau, American Community Survey 2020–2024 5-year estimates, allocated to current linesUpdated Oct 13, 2026, 5:06 AM ET

Seats most like this one

Nearest seats on demographics, density and lean.

District 84
70% college gradsD+78.2Held DDistrict 131
55% college gradsD+72.5Held DDistrict 85
78% college gradsD+81.4Held DDistrict 87
72% college gradsD+70.8Held D

Source: Census Bureau, American Community Survey 2020–2024 5-year estimates, allocated to current lines; 99chambers: 2024 and 2020 presidential results on current lines, relative to the nation (2024 weighted 3:1)Updated Oct 16, 2026, 5:19 AM ET

Who has held it

These lines took effect in 2022.

  1. Democratic (D)
    2027– · Won 2026 unopposed
  2. Samantha Monta O. (D)
    2025–2027 · Won 2024 unopposed

Source: Past results: 99chambers results archive (MEDSL, Klarner, state election offices)