THE Supreme Court decision to allow Mr Des Hanafia's appeal is "justice deferred rather than justice denied", according to Ms Mags O'Brien of the Action Group.
She said that February's High Court dismissal of his challenge to the referendum result was damning.
"The fact that there were three High Court judges who voted against it doesn't seem to indicate much hope." She said she had been in court for both hearings.
"It would be very difficult, even based on the evidence, to decide what effect the advertising had, and at what stage."
Mr Gerard Casey, vice chairman of the No Divorce Campaign, said he was still hopeful the referendum, result could be overturned. "We always knew it was going to be a long haul".
He said the appeal would be based on the Supreme Court ruling, in the case taken by Ms Patricia McKenna MEP. In November the Court ruled that the Government funded advertising campaign for a Yes vote was unconstitutional.
"We will be bringing back our judgment to the court and saying Here, what do you make of that?". He said the Supreme Court had shown a "willingness to go against expectations" in that judgment.
Mr Casey said the No Divorce Campaign had not wound up officially since the referendum. "We may stay together to monitor the divorce legislation."
A legal source said yesterday's decision was not surprising. "The judges gave all the signs of giving him (Mr Hanafin) a right to appeal during the hearing and the fact that they delivered a judgment so quickly meant there was no doubt."
However, he said, the feeling was that the appeal would be lost. "The Supreme Court can't interfere with findings of primary fact."
Mr Hanafin said he was not in a position to comment, other than to say he was pleased with yesterday's decision and hopeful about the appeal. He had not celebrated the decision last night, he said.
"I came home terrible tired and went to bed."