Nationalist party Sinn Fein won the popular vote in Ireland’s general election, ballot counts revealed Sunday, with the one-time political wing of the IRA disrupting a duopoly of centre-right parties which have historically controlled the Republic. After all 39 constituencies across Ireland were tallied Sinn Fein received 24.5 percent of the first preference vote, outstripping the opposition Fianna Fail party on 22.2 percent and incumbent prime minister Leo Varadkar’s governing Fine Gael party on 20.9 percent. Ireland operates on a single transferable vote system and Sinn Fein ran a slate of just 42 candidates for the 159 seats contested, meaning its strong performance may not result in it becoming the biggest party in Ireland’s next parliament. But the left-wing party started celebrating its surge after campaigning on issues of healthcare and housing. “It’s official (Sinn Fein) won the election — highest popular vote,” tweeted leader Mary Lou McDonald. Counting is expected to continue on Monday, with analysts saying it could take two to three days before full results are known. Ending the duopoly Fine Gael and Fianna Fail have traditionally taken turns in power in the Republic. “It seems that we have now a three party system,” said Varadkar at the counting centre for his Dublin West constituency. “That is going to make forming a government quite difficult.” Varadkar failed to take the first of four seats as the count unfolded, with a Sinn Fein candidate announced as the first new lawmaker in his region. Varadkar was elected on the fifth round of vote counts, relying on redistributed ballots in a morale-bruising episode for the premier. At 2315 GMT state broadcaster RTE reported that 60 of 159 seats were filled, with 29 going to Sinn Fein. But due to ballot transfers and Sinn Fein’s smaller slate of candidates an overall seat forecast should not be extrapolated from the early set of lawmakers elected.