The gap is expected to be far shorter than the 11-month hiatus that followed the death of ex-minister Seamus Brennan and the landslide election of Mr Lee.
Fears over the Government’s record unpopularity meant Fianna Fáil put off the election for as long as it could last time. However, the electoral timetable this year could force their hand.
Green Environment Minister John Gormley insists new legislation is still on-course to produce a vote for a directly elected Dublin mayor in June.
To avoid additional costs, this would prove a natural juncture to hold the by-election in Dublin South.
But, serious doubts remain over whether Mr Gormley will be able to get his legislation through in time for a summer poll, with September or October looking more likely. It is highly unlikely the Dáil vote would be held separately to the mayoral one. The other logical trigger for the Dublin South poll would be to link it with an expected referendum on children’s rights which has been pencilled in for early autumn.
An election for the vacant Dáil seat in Donegal South is also likely to be held the day of the referendum.
The seat has been without its full quota of TDs since Pat “the Cope” Gallagher was rushed into the Euro MP race to prevent a Fianna Fáil humiliation in the North West constituency in June of last year.
Fianna Fáil is delaying a Dáil showdown there as Sinn Féin is hotly tipped to challenge hard for the seat. A victory by the latter would make the Government’s already precarious majority in even more danger of being overturned.
A voter backlash against Fine Gael in Dublin South could hand the seat to veteran Labour candidate Alex White.