A new opinion poll suggests that Fianna Fáil has a three-point lead over Fine Gael, while Sinn Féin has secured a six-point increase in support.
The Behaviour and Attitudes survey, for the Sunday Times, also suggests a two-point drop in support for both the Green Party and Labour since their last poll in July.
Fianna Fáil is down one to 29% with Fine Gael unchanged on 26%.
Sinn Féin is up six points to 20% with Labour down two to 3%.
The Green Party is down two points to 5%, Solidarity/PBP down one to 1% and Renua up one to 1%.
The Social Democrats are unchanged on 1%, with the Independent Alliance also unchanged on 4%.
Aontu shows no change on 0% with Independents up one to 9%.
The fieldwork for the poll was conducted between 5-17 September and has an accuracy of plus or minus 3.3%.