99chambers

California State Assembly seat · lines in effect since 2022

California Assembly District 31

A district of about 500,000 people, 63% Hispanic, 17% of adults with a bachelor's degree. It votes D+17.5 relative to the nation for president.

Joaquin Arambula (D) · since Nov 2, 2004Next election Nov 7, 2028The 2026 race →

Where it sits among all 80 seats

Every California State Assembly 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+17.549th most
Democratic
Most DemocraticMost Republican41st seat · the majority lineDistrict 31

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.

202220242026
California State AssemblyD+21.6D+20.5D+35.6

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

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

Who lives here, compared

Grey bars show the spread of all 80 seats. Small marks are other seats in California. The black marker is District 31.

Adults with a bachelor's degree17% 8th pct · 74th of 80 in CA

Lower than 92% of seats.

White adults without a degree16% 42nd pct · 47th of 80 in CA

Lower than 58% of seats.

Hispanic residents63% 78th pct · 18th of 80 in CA

Higher than 78% of seats.

Black residents5% 67th pct · 27th of 80 in CA

Higher than 67% of seats.

Asian residents12% 57th pct · 35th of 80 in CA

Higher than 57% of seats.

People per square mile863 38th pct · 50th of 80 in CA

Less dense than 62% 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. 1 of the 4 flipped this year.

District 53
67% Hispanic · 22% college gradsD+16.8Held DDistrict 50
62% Hispanic · 25% college gradsD+14.0Held DDistrict 58
63% Hispanic · 22% college gradsD+8.1Flipped DDistrict 80
64% Hispanic · 27% college gradsD+21.6Held 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. Annalisa Perea (D)
    2027– · Won 2026 by 35.6
  2. Joaquin Arambula (D)
    2023–2027 · Won 2022 by 21.6, 2024 by 20.5

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