A candidate who was part of an unprecedented write-in campaign in November won a seat on the West Chester Area school board, according to official results certified Wednesday.

Sue Tiernan, a retired educator and school administrator, won the last of five seats on the nine-member board that were up for election.

The other four winners - Maureen Snook, Linda Raileanu, Vincent Murphy, and incumbent Karen Miller - were on the Republican slate.

Tiernan is part of a movement of moderate Republicans, Democrats, and independents that calls itself West Chester VOTE. It fielded an independent slate of candidates to counter what it said was a recent conservative turn on the school board.

It garnered more than 40 percent of votes cast.

"I am humbled by the support and the results of the write-in campaign effort," said Tiernan, a lifelong West Chester resident.

With 7,690 votes, she beat the nearest Republican challenger, Galen Plona, a Westtown resident who came in seventh, by 193 votes, according to the official tally.

Gary Bevilacqua, a West Chester VOTE candidate also of Westtown, came in sixth with 7,550 votes.

Tiernan's election marks the first time in recent memory that a non-Republican candidate will take a seat on the school board. Tiernan is a Democratic committeewoman and has said she will step down from that post upon taking office.

County Republican Chairman Val DiGiorgio said the party was reviewing the election results but didn't anticipate a legal challenge.

Contact staff writer Anthony Campisi at 215-854-5015, acampisi@phillynews.com, or @campisa on Twitter.