DUBLIN — Ireland has taken a decisive step to the left in local and European elections, where early returns on Saturday showed that the big winners were Sinn Fein, formerly the political wing of the Irish Republican Army, and Socialist independent candidates.

After almost seven years of economic austerity, voters vented their anger toward the government coalition parties, Fine Gael and Labour, blaming the latter in particular for its perceived failure to protect not only the interests of the poor but also its lower-middle-class supporters.

“Sinn Fein and independents have been the principal winners in this election,” the communications minister, Pat Rabbitte, told reporters as it became apparent that his Labour Party had been decimated. “The longevity of the recession is the worst we have seen and people are saying, ‘Enough is enough.' ”

Although final results were not expected until Sunday, exit polls and early results on Saturday indicated that support for Labour had slumped to 7 percent of the vote from 19 percent in the last general election, in 2011. In contrast, support for Sinn Fein rose to about 17 percent from 10 percent, according to early results and exit polls. That put Sinn Fein only 5 percentage points behind Fine Gael, the dominant party in the current government, whose support fell 7 percentage points compared with 2011.