Voter registration As of June 12, 2023, there are 70,553 registered voters in the county. Republicans hold a plurality of voters by a margin of 10,354 voters (14.67% of the total registered). There are 35,735 registered
Republicans, 25,381 registered
Democrats, 7,319 registered
non-affiliated voters, and 2,118 voters registered to
third parties.
Political bellwether Mercer County was previously considered a political bellwether for the state of Pennsylvania since its demographics, urban-rural ratio, and party affiliation once closely mirrored the state as a whole. In
2000,
Al Gore carried it against
George W. Bush. This trend failed to hold true in
2004 and
2008, in which Mercer County voted more conservatively than the rest of the state. In 2004, Bush won Mercer County with 51% of the vote. That year,
John Kerry won the state as a whole with 51% of the popular vote. In 2008,
John McCain won Mercer County by fewer than 200 votes, as he and
Barack Obama each received roughly 49% of the popular vote. Obama won Pennsylvania as a whole with 55% of the popular vote. Each of the three statewide office winners also carried Mercer in 2008. In
2016,
Donald Trump won Mercer County by 12,403 votes, and he also won all of Pennsylvania. Each of the three Republican candidates for statewide office carried Mercer County in 2016. In
2020, Trump again carried the county, despite Pennsylvania narrowly voting for
Joe Biden. Trump won 62% of the vote, the largest majority for any major party candidate since
1964, and the largest majority for a Republican since
1928.. In
2024, Trump won the county for a third time, receiving 64.45% of the vote, and breaking the record set in the last election.
County officials State House of Representatives State Senate United States House of Representatives United States Senate ==Education==