GOVERNMENT senators are admitting they may vote against coalition measures if the referendum to scrap the Upper House is passed on Friday.
As campaigning enters its final few days, Transport Minister Leo Varadkar claimed the Seanad costs an official in his department a full nine weeks' work – worth €15,000 – a year.
Mr Varadkar claimed this would translate into thousands of needless hours across the entire civil service when other departments were included.
But the Government's plans for the rest of its term could be thrown into disarray if Fine Gael and Labour senators vote against measures like the Social Welfare Bill.
The Senate can only delay bills by 90 days, but this could still cause chaos.
If the referendum is passed, the Seanad will not be abolished until the day before the new Dail convenes after the next general election. But Labour senator Mary Moran – who took part in a press conference of TDs and senators calling for a No vote – said government senators would be "freer" to vote as they wished.
"The Seanad has a very real purpose here, we will be freer, if you like, to exercise our will," Ms Moran said.
It comes as Mr Varadkar claimed the Seanad costs his department 344 staff hours a year, which he said was worth €15,000 annually.
He claimed the Seanad racked up hidden costs in "every arm of government", and probably more staff hours in busier departments, such as Finance and Social Protection.
"The servicing of Seanad business took up 344 hours in my own department alone over the last year," Mr Varadkar told the Irish Independent.
"But other departments like Justice or Public Expenditure and Reform have to devote much more time to the Seanad.
"So it's likely that the Seanad uses up between 5,000 and 10,000 staff hours in the entire civil service every year."