Seventy-one Fianna Fail TDs will vote on Taoiseach Brian Cowen's position as leader tomorrow.
Mr Cowen is dispensing with procedure and putting forward a motion of confidence in himself at the parliamentary party meeting to resolve the issue surrounding his leadership.
Under normal Fianna Fail rules, a leader would only face a vote on the leadership if a quarter of the TDs in the party -- 18 at the moment -- put forward a motion of no confidence.
In the case of a motion of no confidence, the vote has to be taken at least five days later.
Senators are not entitled to vote on the leadership.
Tomorrow's meeting of the parliamentary party is expected to take place at the normal teatime slot in the party rooms on the fifth floor of the Leinster House complex.
Mr Cowen's calling of a motion of confidence in himself is reminiscent of Fine Gael leader Enda Kenny's move last year.
It was also a tactic employed by Charlie Haughey when he sensed the rebels were gathering strength. Mr Haughey was a master of manipulating the party in heaves -- even though the ineptitude of his opponents was often the key to his victories.
The strategy is regarded as being of advantage to the party leader as it makes it psychologically more difficult for a TD to directly vote against the leader.
The difference between a confidence vote or a no confidence vote may seem narrow, but casting any doubt into a TD's mind is deemed to be significant.
Cutting off the tabling of a motion of no confidence also ensures there won't be a quarter of the TDs declaring against the party leader to start with.
Mr Cowen also has the advantage of knowing there are a number of TDs who believe a leadership contest at this time would be divisive for the party.
A number of middle-ground TDs are of the view it is too close to the general election to be changing the party leader.