Post Office candidates will run in the next election after members voted in favour of the move.
Members of the Irish Postmasters' Union have agreed to a comprehensive political campaign at their annual conference in Kilkenny, that they say will protect the post office network.
The motion was presented by members of the Ballina branch.
The candidates will run in next year's General Election as Independents, but will be supported by the 1,100 post offices across the country.
Concern about the future of the post office network has intensified recently, after a report by Grant Thornton found hundreds of offices nationwide would close by 2017, mainly as a result of the change in the delivery of social protection payments to Electronic Funds Transfer.
General Secretary of the Postmasters' Union Ned O'Hara said the motion was passed due to a "sense of frustration in relation to the damage being done to their communities - the communities they serve. They feel people just aren't listening to them.
"They get lots of promises (from TDs and Ministers), but very little concrete action."