Pennsylvania State Senate seat · lines in effect since 2022
Pennsylvania Senate District 21
A district of about 257,000 people, 23% of adults with a bachelor's degree. It votes R+42.9 relative to the nation for president.
Where it sits among all 50 seats
Every Pennsylvania State Senate seat by partisan lean, from most Democratic to most Republican. Lean is the seat's presidential vote on current lines, relative to the nation.
Democratic
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.
| 2016 | 2018 | 2024 | |
|---|---|---|---|
| U.S. Senate | R+35.3 | R+22.7 | R+35.1 |
| Governor | No race | R+19.5 | No race |
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 50 seats. Small marks are other seats in Pennsylvania. The black marker is District 21.
Lower than 92% of seats.
Higher than 96% of seats.
Lower than 94% of seats.
Lowest of 50 seats.
Lowest of 50 seats.
Less dense than 96% 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 2324% college gradsR+42.2Not up in 2026District 41
23% college gradsR+40.6Not up in 2026District 30
20% college gradsR+51.1Held RDistrict 32
PennsylvaniaR+49.6Held R
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