His victory was one of the closest of the elections, beating Fianna Fáil's Tom Cox by 40 votes.

[2] He worked on various campaigns ranging from Quality Bus Corridors to better sewage treatment and waste management facilities.

He is a campaigner for the Western Railway Corridor, Light rail for Galway and water quality issues.

Ó Brolchain was nominated as the Green Party candidate and received the backing of coalition partners, Fianna Fáil.

He works as a research associate at the Insight Centre for Data Analytics (formerly DERI) in NUI Galway.