BERTIE AHERN is elected taoiseach and puts together a government of Fianna F�il and the PDs, supported by independents.

With the breakdown of the FF-Green negotiations, this is Fianna F�il's fallback position. Between them, Fianna F�il and the PDs have 80 seats and it seems likely they will obtain the support of independents Beverley Flynn, Jackie Healy-Rae, Michael Lowry and Finian McGrath. With Sinn F�in possibly abstaining and a Labour TD likely to become ceann comhairle, Ahern would comfortably have the numbers to become taoiseach for a third time.

Likelihood: Very possible Scenario number two AHERN is elected taoiseach and puts together a government of FF, the Greens and the PDs, buttressed by two or three independents.

Until just after 5pm on Friday, this seemed the most likely outcome but the breakdown of the talks changed everything. However, it is believed still to be Bertie Ahern's favoured option.

Informal contacts between FF and the Greens are going on this weekend and it is still possible that negotiations between the two will resume over the next day or so.

However, in the event of a deal being put together on Monday, it would mean the Greens holding a convention on Tuesday or Wednesday night. They are reluctant to hold a convention on a weekday but, if a deal were agreed, would they really pass up the opportunity of government for this reason?

Unquestionably though, the Greens will need to show their members at the convention that this is a new government with a decidedly Green tinge.

Likelihood: Still possible.

Scenario number three Nobody is elected taoiseach on Thursday. This is being discussed as a very possible scenario, but unless the PDs opt not to vote for Bertie Ahern, it is hard to see how he will fail to get 83 or 84 votes.

Even without the PDs, it seems that Fianna F�il will have 82 votes - its own 78 plus four independents - which if Sinn F�in abstains would be enough to elect Bertie Ahern (although it would not be enough for stable government).

If Bertie Ahern did fail to be elected taoiseach, it raises the possibilities of Fianna F�il and the Greens resuming negotiations. Fianna F�il and Labour might even begin to talk, as Labour - having voted for Enda Kenny for taoiseach - would be free of its obligations under the Mullingar accord.

Likelihood: Still very hard to see it happening.

Scenario number four Nobody is elected taoiseach on Thursday and Enda Kenny sets about forming an alternative Rainbow coalition.

But even assuming the PDs decide to vote for Kenny rather than Ahern, which seems a big stretch, the combined strength of FG, Labour, Greens and the PDs is just 79 seats.

So unless they give the ceann comhairle job to Sinn F�in or, even more unlikely, do a deal with Sinn F�in, the Rainbow would need the support of all five independent TDs. It is simply impossible to imagine Beverley Flynn or Jackie Healy-Rae voting against Bertie Ahern and in favour of Enda Kenny for taoiseach.

Likelihood: Stranger things have happened, but not much stranger.

Shane Coleman