One of the country's biggest trade unions has urged the Labour Party to reject a coalition with Fine Gael in favour of a left-wing government.
Unite, which is affiliated to the Labour Party, called on its 60,000 members to vote for and transfer to leftist parties in the forthcoming general election.
Jimmy Kelly, the union's regional secretary, suggested Labour and Sinn Fein could form the State's first left-wing government along with support from independents.
"Recent polls put the combined strength of the Labour Party and Sinn Fein at 40%," he said.
"This is substantially higher than either of the right-wing parties.
"With the support of other left parties and progressive independents, a left government is now distinct possibility."
Last week, Labour leader Eamon Gilmore rejected advances from Sinn Fein president Gerry Adams on an alliance.
But Mr Kelly said although there would be competition between left-wing parties for votes, they had more in common with each other than they had with either Fine Gael or Fianna Fail.
The union leader said both larger parties had similar policies, supporting privatisation, more job losses and massive cuts to public services and social welfare. He said: "For the first time we have an opportunity to move away from out of touch and outdated politics based on history rather than ideology."
The latest Red C opinion poll showed Fine Gael as the largest party in the State, on 35%, with Labour on 21% and Fianna Fail and Sinn Fein tied on 14%.