The 32nd Dáil will have 158 TDs, which is eight fewer than the current number of 166.
As a result, once the Ceann Comhairle is excluded, 80 seats will be required to hold a majority.
As things stand, with a year to go to when the election must be held, Fine Gael is targeting 30pc of the vote.
This, it says, would deliver between 60 and 63 seats, a good deal short of an overall majority.
Party strategists are hoping the Labour Party can continue its upward trend in the polls and get at least 10pc of the vote.
Such a return would give Labour in and around 20 seats, depending on transfers. This would see the Coalition returned.
But FG is openly talking of a possible "New Gregory deal" with some sympathetic independents, which would see it over the line.