Fears of a shock defeat in the marriage referendum are growing within Fine Gael after TDs said they had encountered a strong "silent No vote" in rural areas.
Fine Gael bosses have become extremely anxious about the referendum in recent days, due to the negative feedback being received by party headquarters.
Rural TDs and senators say party supporters are being increasingly challenged over the impact a 'Yes' vote may have on the rights of children.
Some TDs have warned that supporters were becoming "disheartened" at the reaction of voters in rural areas.
Other deputies have said privately that they were dedicating more time to campaigning in the Carlow/Kilkenny by-election than for a 'Yes' vote for same-sex marriage.
Speaking to the Irish Independent, over a dozen Fine Gael TDs confirmed they were encountering difficulties while canvassing for a 'Yes' vote.
Senior party sources said Fine Gael would increase the resources dedicated to their campaign to try and avoid a defeat on May 22.
A 'No' vote would prove to be an absolute disaster for the Government and Taoiseach Enda Kenny, who has already faced criticism for failing to take part in live debates.
While Fine Gael members are receiving a positive response in urban areas, especially Dublin, their colleagues in rural parts of the country are struggling.
Former junior minister Ciarán Cannon said he believed voters were "exceptionally confused" due to the tactics of 'No' campaigners. "The 'No' campaign are exceptionally cynical with their postering, raising issues such as surrogacy and adoption. People are being told a 'Yes' vote will undermine children's rights and that approach is working," the Galway East TD told the Irish Independent.
Clare TD Pat Breen said he was surprised at the strength of the "silent No vote". Mr Breen said upon meeting such members of the public, it becomes clear they intend to vote 'No'.
"We have to be honest. There is a silent number of Fine Gael members and supporters who won't be voting for it either," he added.
Meath West TD Ray Butler said the result was "not a foregone conclusion", adding that elderly people in particular were strong advocates of a 'No' vote.
"There are people who are not overly happy with the stance of Fine Gael," he said.
"There is no point saying otherwise, there is no point saying there's 100pc agreement on this," he added.
Cavan/Monaghan TD Sean Conlan warned of "soft Yes voters" in rural Ireland who would need further convincing ahead of the referendum.
The negative feedback from TDs has caused concern at senior level in Fine Gael, two separate strategists confirmed last night. While it was initially feared some TDs and senators would refuse to campaign, the party is now more concerned about the reaction being fed back to headquarters.
Donegal TD Dinny McGinley said voters were "fairly divided".
Kerry TD Brendan Griffin said he had encountered thousands of different opinions on the doorsteps.
"There are concerns about children. People are afraid of a situation whereby the rights of children are drastically changed. We must learn lessons from the children's referendum. This could be quite tight, we need to be careful," he added.
Views within Fine Gael are also divided over whether the Taoiseach should take part in a live television debate.
Launching the Fine Gael campaign last month, Mr Kenny said he does not believe the campaign should be about political leaders, a clear indication of his intention not to take part in such a debate.
Agriculture Minister Simon Coveney, Fine Gael's campaign director, urged TDs and senators to work hard to deliver a 'Yes' vote at the parliamentary party meeting last week.
A number of regional campaign directors were put in place in a bid to bolster Fine Gael's campaign.
Finance Minister Michael Noonan said at the weekend the 'Yes' campaign was deliberately "low key" so as to connect with voters.
Asked about the Catholic Church's call for a 'No' vote, Mr Noonan said: "Everybody is entitled to say what they think in this campaign. I think it's a very polite campaign so far."