A motion urging the party to introduce a system of directly-elected mayors whenever it returns to government was rejected after a councillor implied that voters would not elect Fine Gael mayors if they would not elect TDs for the party.
Senior party figures such Mr Bernard Allen TD and Senator Jim Higgins had spoken in favour of motion, which condemned the PDs for acquiescing to Fianna Fáil's decision to reverse its commitment to provide for directly-elected mayors.
But, after the session chairwoman, Ms Avril Doyle MEP, indicated that she believed there might be alternative views in the audience, many delegates signalled support for the retention of council-elected mayors when she sought a show of hands.
Ms Doyle, who said she was going "off script and into deep trouble", then asked for a contribution from the floor.
Cllr Rainsford Hendy, from Kildare South, said he had been elected mayor by his local council even though Fine Gael held only six of the 25 seats on the council.
Fine Gael would "never ever" occupy the position of mayor in his constituency under a system of directly-elected mayors, he said.
Mr Allen claimed in his speech that the Government had "failed communities" by breaking its commitment to introduce directly-elected mayors.
Mr Higgins, one of the party's European election candidates in the North-West constituency, said the Government had turned its back on the proposal for directly elected mayors as soon as its fortunes reversed in the opinion polls.