The survey revealed almost two-thirds of Scottish voters believe Caledonian MacBrayne services should remain in the public sector while only one in ten supports privatising it.
The independent poll, carried out by Survation, also found that almost six out of ten people support the right of CalMac staff to take industrial action over staffing levels, jobs and pensions, while one in five opposes the workers.
It comes after strike action last month as CalMac staff sought reassurances over the future of the Clyde and Hebrides operations.
A tendering process is under way that could see routes change hands from the publicly owned company to private firm Serco.
The RMT union today vowed to step up its campaign to keep CalMac in the public sector.
General secretary Mick Cash said: “The fact that nearly two-thirds of Scottish voters support RMT’s campaign to keep CalMac as a public service within the public sector is a massive boost for our fight to defend these lifeline ferry routes.
“The message from the general public could not be clearer and is backed up by broad political support for public ownership of CalMac.
“The union expects those overseeing the tendering process to take this resounding, independent polling fully into account and to secure the future of CalMac in the public sector.”
The poll, involving 1,084 people, was carried out online between 3 and 7 July.
It revealed 64 per cent agreed with the statement “the Scottish Government should decide that these ferry services remain publicly operated”.
The RMT union had planned a further day of action for last Friday, when workers were asked not to book on to shifts, but this was suspended.
Mr Cash said that following discussions with the Scottish Government, the tendering process has been delayed to allow further negotiation on the issues of jobs, staffing, conditions and pensions.
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