A new opinion poll shows support for Sinn Féin has surged to 35%.
This is 10 points higher than its general election result in the first opinion poll held since the vote.
The survey was conducted by Behaviour & Attitudes for The Sunday Times.
Fine Gael is down almost three points to 18%, Fianna Fáil is down two to 20% and The Green Party is down one to 6%.
While The Labour Party is down one to 3%, Solidarity/People Before Profit is unchanged on 3% and the Social Democrats are down one on 1%.
Sinn Féin's support seems mirrored in party leader satisfaction: Mary Lou McDonald is up 13 points to 53%.
This is 22 points ahead of her nearest rival, Fianna Fáil leader Michael Martin, who is on 31% - a 15 point drop.
The acting Taoiseach Leo Varadkar has seen his satisfaction rating down eight points to 27%.
Overall government satisfaction has also dropped nine points to 21%.
This latest poll also suggests that the percentage of undecided voters sits at just 13% - the lowest level since this series of polls began in 2011.
The results are likely to put more pressure on Fianna Fáil and Fine Gael to negotiate a government as they prepare to meet this coming week to discuss policies.
The alternative appears to be a second election, in which both parties would lose further Dáil seats.