Labour Party leader Brendan Howlin has said the four upcoming by-elections will give a real indication of the vitality of each political party, and argued that Labour is in a good position to increase its number of Dáil seats.
Elections will take place in four constituencies on 29 November to replace TDs who were elected to the European Parliament in May.
Speaking on RTÉ's This Week, Mr Howlin said the party has deep roots in "parts of the country" and has recovered ground in this year's local elections.
He said the mood in the party is good and there was "tremendous vitality and confidence" at the party's annual conference this weekend in Mullingar.
Mr Howlin has urged Labour voters to give their second and third votes to the Green Party, independent and Social Democrat candidates and said people want an alternative to what he called the "Fianna Fáil and Fine Gael partnership".
Mr Howlin said that in doing so he hoped to form a "progressive force" without preconditions that is capable of forming a critical mass.
He said sufficient numbers are needed to change the political agenda to have a focus on economic fairness and equity and that Labour in government would build 80,000 social and affordable houses over five years, costing €16bn, on public lands and in State ownership.
Mr Howlin also called for the Low Wage Commission to increase the minimum wage to two-thirds of the average wage of €36,000.
He said he would seek collective bargaining rights to break away from "the gig economy" and stop the casualisaton of work.