A new poll suggests that support for Fine Gael has fallen by four points, which is the party's lowest showing in this series of polls.
Independents and smaller parties are most popular among voters.
There were also increases in support for Sinn Féin.
The Sunday Business Post/ Red C opinion poll was carried out on Monday, Tuesday and Wednesday and more than 1,000 people were asked who they would like to see elected to the Dáil, if they had a chance to do so right now.
The poll indicates Fine Gael is down four points to 22%, with Fianna Fail unchanged at 18%.
The Labour Party is also unchanged at 8%.
The poll found support for Sinn Féin is at 22%, an increase of two points, indicating the party's support is level with Fine Gael, and coming after sustained criticism in the Dáil over the party's handling of the Máiría Cahill controversy.
The poll also indicates that Independents and smaller parties are the most popular group among the voters surveyed, with support up two points to 30%.
The government parties will hope that Wednesday's announcement on water charges will help them win back favour among the voters that backed them in 2011.