A new opinion poll shows a majority of people are likely to back the abolition of the Seanad.
The survey carried out for Paddy Power by Red C shows 52% in favour, 34% against and 14% undecided.
When the undecided are excluded, the results show 61% are likely to back the autumn referendum with only 39% opposed.
Fine Gael voters are most likely to support the abolition.
On party support, the Red C figures show Fine Gael up four points to 30% and Labour down one point to 10%.
Fianna Fáil is down two points to 24%; Sinn Féin is unchanged at 16%; and Independents and others are down one point to 20%.
The last comparable Red C poll was carried out last month.