The majority is broadly consistent across rural and urban areas, the survey says, with 62pc approval in Dublin and higher support in non-urban locations.
The Red C survey was conducted among 1,000 adults in March.
The National Broadband Plan is the government’s promise to roll out high speed internet access to 540,000 homes and businesses in areas with poor broadband infrastructure. Most of the areas identified for the state intervention plan are in rural locations. Over 1m people would be covered by the roll-out’s population coverage.
However, the cost of the scheme is a consideration for some respondents. One in six say that the plan should only proceed if the taxpayer bill stays below €1.5bn. Most estimates put the final cost of the rollout at around €2bn.
The poll also said that the same number of people believe it should proceed at any cost (19pc) as believe it should not proceed in any circumstances (17pc).
The poll was commissioned by the price comparison site Bonkers.ie.
The National Broadband Plan is currently awaiting a recommendation from Communications Minister Richard Bruton, who said he intends to present the plan to Cabinet before Easter.
Last week, the most senior civil servant working on the National Broadband Plan told the Oireachtas Public Accounts Committee that a fibre rollout was the best way to “future proof” rural homes and businesses for the next 25 years.
Mark Griffin, Secretary General of the Department of Communications, also said that while wireless solutions would likely play some part in reaching a minority of the most remote premises, it was not a preferred technology for a “future proof” rollout.
He said that initial estimates six years ago of €500m for the rural rollout cost were abandoned because they were based on a scheme that was “not fit for purpose”. The original plan, he said, was to run fibre to villages, from where it would connect homes over phone lines or wireless means. But while that might have provided a good enough service for email or basic internet activities today, it would likely not meet the requirements of a business or modern home in 10 years’ time.
However, Mr Griffin declined to say how much the National Broadband Plan would now cost for “commercial sensitivity reasons”.
Taoiseach Leo Varadkar recently said that the plan would cost a multiple of the initial €500m estimate.
Mr Griffin said that the basic speed of a National Broadband Plan service would be 150 megabits per second, with 1,000 megabits per second for schools and businesses.
Asked about timelines, Mr Griffin said that his officials would “finalise the evaluation work and bring a memorandum to government with a recommendation for the appointment of a preferred bidder” but that “there would be a number of contractual issues” outstanding.
He said that if and when a preferred bidder is agreed upon, it would then take “weeks” or longer to sign a contract.
The current delay makes the possibility of connections to a new National Broadband Plan service unlikely in 2019.
Social Democrat TD Catherine Murphy asked whether the competitive tendering process for the National Broadband Plan was at risk by only having one remaining bidder, Granahan McCourt, for the state contract.
“It’s not usual to have a single bidder although it’s not ideal,” said Mr Griffin. “If you look at the UK equivalent of the National Broadband Plan, there was only one final bidder, BT, after Fujitsu pulled out. But it’s always better if you have more bidders in terms of competitive tension.”
Ms Murphy asked whether there were any parallels with the National Childrens Hospital from a cost analysis.
“The fundamental difference between this and the National Childrens Hopsital is in how we reached a situation where a cost estimate was very different from what we thought at the start. The Childrens Hospital is an issue around how cost escalated when construction had commenced.”