The party leader, Mary Lou McDonald, told cheering supporters on Sunday that a “revolution” had occurred and she would try to form a ruling coalition with other parties. “This is no longer a two-party system,” she said.
Sinn Féin, once a pariah for its IRA links, won almost a quarter of first-preference votes, possibly pipping Fine Gael and Fianna Fáil, two centrist rivals that have taken turns ruling Ireland for a century.
It rode a wave of anger over homelessness, soaring rents and hospital waiting lists as well as disillusionment with the traditional political duopoly.
McDonald, speaking over rapturous, deafening chants at a Dublin count centre, said she had spoken to the Greens and small leftwing parties in hope of forming a coalition without Fine Gael or Fianna Fáil – an unlikely scenario. She did not rule out a deal with either Fine Gael or Fianna Fáil.
Parliamentary arithmetic may exclude Sinn Féin from power, however. Fianna Fáil and Fine Gael ran more candidates and are expected to each win more seats than Sinn Féin in the 160-seat Dáil Éireann, the Irish parliament’s lower chamber, leaving unclear which parties – if any – will be able to form a viable coalition. Deadlock could lead to another election.
During the campaign Leo Varadkar, the taoiseach and Fine Gael leader, and Micheál Martin, the leader of Fianna Fáil, both ruled out entering government with Sinn Féin, citing ethical and policy reasons.
On Sunday evening, Varadkar told journalists in Dublin: “For us, coalition with Sinn Fein is not an option, but we are willing to talk to other parties.”
Varadkar, Ireland’s first gay taoiseach, had hoped a healthy economy and his record on Brexit would deliver a third term for Fine Gael, but he encountered voter fatigue and anger over the cost of living and state of public services.
Varadkar’s party colleague Richard Bruton, the outgoing environment minister, said Fine Gael’s poor but not disastrous results gave it a chance of forming another government.
Asked if Fianna Fáil would now consider sharing power with Fine Gael or Sinn Féin, Martin appeared to leave the door ajar, citing a need for stability amid political fragmentation. “The country comes first … there is an onus and an obligation on all that such a functioning government is formed after this.”
Many in Fianna Fáil, stung by the backlash over their confidence-and-supply deal with Varadkar’s outgoing government, would prefer a deal with Sinn Féin than another centrist alliance.
Ireland’s single transferrable vote system of proportional representation means it could be Monday, Tuesday or even later before all Dáil seats are allocated.
With 96% of first-preference votes tallied on Sunday, Sinn Féin had 24.1%, with Fianna Fáil on 22.1%, Fine Gael on 22.1%, Greens on 7.4%, and small leftwing parties and independents comprising the rest.
It was a stunning result for Sinn Féin, which was the IRA’s political wing during the Troubles and remained a fringe party in the republic until well after the 1998 Good Friday agreement.
It surpassed its 2016 election result of 13.8% by appealing to voters – especially the young – who felt left behind by a booming economy and chafed at soaring rents, homelessness, insurance costs and hospital waiting lists.
Preliminary vote tallies suggested Sinn Féin could win around 36 seats, up from 22 in the outgoing Dáil, far exceeding its own expectations.
Many candidates ratcheted up huge surpluses in urban heartlands while others appeared on course for unexpected victories in Galway, Tipperary, Roscommon, Mayo and Wexford.
Gerry Adams, who stepped down as party leader in 2018 and as a Dáil member in this election, credited McDonald’s leadership and said he had not foreseen the extent of the gains. He said Sinn Féin would use its mandate to plan for a united Ireland – a defining tenet for the party.
The issue barely featured in the campaign, but an exit poll of voters found most supporting a border poll in the next five years. Sceptics say that could destabilise both sides of the island. Unionist leaders in Northern Ireland gave no immediate response to the results south of the border.
People across the political spectrum said the election was seismic, even if its consequences remained unclear. The former Labour leader Pat Rabbitte said a tectonic shift had killed the old system of Fianna Fáil and Fine Gael alternating in power with Labour or other small, establishment parties.
The commentator Fintan O’Toole wrote in the Irish Times that young voters had shattered the taboo of backing a party associated with terrorism. “They have gone where they were warned not to go and in doing so they have redrawn the map of Irish politics to include territory previously marked ‘here be dragons’.”