A substantial majority of voters favour the abolition of the Seanad, although the margin has declined a little since February, according to the latest Irish Times/Ipsos MRBI poll.

The poll also shows that a majority of voters are opposed to reducing the voting age to 17 as proposed by the constitutional convention.

On the question of how they intend to vote on the Government’s proposal to abolish the Seanad, 55 per cent said they would vote Yes; 21 per cent said they would vote No and 24 per cent had no opinion. When the undecided voters are excluded, 72 per cent would vote Yes and 28 per cent No.

The recent debate on the issue, including the launch of a campaign against the Government’s proposal, appears to have had very little impact on public opinion to date.

When voters were asked the same question in February 58 per cent said they would vote Yes, 20 per cent No and 22 per cent had no opinion.

In this week's poll the strongest support for the proposed abolition comes from Fine Gael supporters, 62 per cent of whom back it. Labour supporters are less enthusiastic with 51 per cent in favour.

Despite Fianna Fáil’s opposition to the plan, 52 per cent of party supporters support abolition while 57 per cent of Sinn Féin voters are in favour with the same figure for those who support Independents and Others.

In class terms the divide is closest among the best-off AB voters who split 54 per cent in favour and 31 per cent against. The strongest support for abolition comes from the poorest DE category with 58 per cent to 15 per cent in favour.

Across the age groups younger voters aged between 18 and 24 are the weakest in their support for abolition but a large proportion of them are in the undecided category.

With about four months of campaigning ahead the Government is in a strong position to carry a Yes vote but the result is not a foregone conclusion. The No vote is strongest among the best off and most educated voters while it is weakest among the poorest voters.

Given that the better-off voters are much more likely to cast their votes, the result could ultimately hinge on the level of turnout. The key battleground will be the middle class electorate which appears more open to voting No.

While a majority of voters oppose the proposal by the constitutional convention to reduce the voting age to 17, but the poll shows a majority in favour of five other recommendations for constitutional change made by the convention.

On the proposal to reduce the voting age, 62 per cent of people said they would vote No, 34 per cent said they would vote Yes and 4 per cent had no opinion.

Strongest opposition to the reduction of the voting age came from Fine Gael supporters with Sinn Féin voters the most strongly in favour. In age terms there was little variation from the 18 to 25 year olds up to the over 65s with all of them decisively against a reduction.

The next most contentious issue was the proposal to reduce the president’s term from seven years to five. It was supported by 52 per cent of voters with 41 per cent against.

On the question of same-sex marriage, there was strong support for the proposal with 69 per cent Yes and 25 per cent No. Women were much more strongly in favour of the proposal than men while Fianna Fáil voters were more strongly against than supporters of other parties.

On the proposal to give the vote in presidential elections to Irish citizens living abroad, there was strong support with 72 per cent for and 22 per cent against. There were no wide variations across the different groups.

Asked about removing the reference in the Constitution to a woman’s life within the home, 49 per cent were in favour with 17 per cent against and a substantial 34 per cent having no opinion.

On the question of removing blasphemy from the Constitution, there was also a sizeable undecided group with 30 per cent having no opinion compared to 50 per cent in favour and 20 per cent against.

The survey was undertaken last Monday and Tuesday among a representative sample of 1,000 voters aged 18 and over, in face-to-face interviews at 100 sampling points in all constituencies.

The margin of error is plus or minus 3 per cent.