Labour's Eric Byrne topped the poll in Dublin South Central having lost on out a seat in 2007 by 69 votes.
Mr Byrne took 8.357 first preference votes, while Sinn Féin's Aengus Ó Snodaigh, who won the last seat from Mr Byrne in 2007, was second with 13.49 per cent of the vote.
United Left Alliance candidate Joan Collins, who took nearly 13 per cent of the first preferences, was also elected. .
Labour brought in a second seat with local councillor Michael Conaghan. The third Labour candidate, Henry Upton, failed to retain his aunt Mary Upton's seat, who has retired.
Incumbent Fine Gael TD Catherine Byrne retain her seat, but Fianna Fáil's Michael Mulcahy lost his.
The overwhelmingly working-class constituency, which has been dubbed the independent socialist republic of Dublin South Central, polled 61 per cent of votes for left-leaning candidates.