County record · fips 42085 · Pennsylvania
MercerPA
Republican ×6 since 2004all 40 elections, 1868–2024
The Long Record
40 elections against the Pennsylvania and national vote
2024 result
R+30.4
won by Republicans
Record since first cycle
10–30
Dem–Rep two-party wins
Voted with the winner
27/40
68% of its elections
Closest election
2008
R+0.3
this countyPennsylvanianational (official)dot colour = two-party winner · hollow = tie or unknown total · click a dot to open that election
The Biggest Swings
Cycle-over-cycle change in the two-party margin, in points
| Election | Swing | Toward |
|---|---|---|
| 1920 | -45.5 pts | Republicans |
| 1912 | +45.2 pts | Democrats |
| 1964 | +37.0 pts | Democrats |
| 1932 | +34.4 pts | Democrats |
| 1916 | -32.4 pts | Republicans |
Who Lives Here
Census & ACS county profile, 2024
Population
109,257
College (BA+)
26%
Median income
$59,976
2024 dollars
Non-white
12%
Rural
48%
Age 65+
23%
Interpolated between Census/ACS anchors; income CPI-deflated to 2024. Demographics begin in 2000 — earlier cycles have returns only.
Neighbouring counties
Mahoning, OH · Trumbull, OH · Butler, PA · Crawford, PA · Lawrence, PA · Venango, PA