Getting the results you want:PR enables the Irish voter to influence three key issues, writes Stephen Collins,Political Editor
One of the beauties of the Irish PR system is that it allows people to vote tactically for the government they want to see in power, the parties they favour and the individuals they like.
The system also allows the voter to indicate a preference between the candidates or parties he doesn't like, in terms of which he dislikes the most.
As regards government formation the tactical voting choice is relatively simple. Fianna Fáil supporters should vote for their own party's candidates first and continue their next preference to the Progressive Democrats, if they want to see the current Government returned to office.
PD voters looking for the same outcome should do the same thing in reverse, voting first for their own party and continuing their preferences to Fianna Fáil. If they want to vote PD but really want a change of government, they should continue their preferences for another party.
The same applies to Fianna Fáil voters who would like to see their party in coalition with a party like Labour or the Greens instead of the PDs.
Voters who want a change of government as a top priority should vote for Fine Gael and Labour, the order depending on which party they favour most. Supporters of each party should continue their preferences to the other to maximise the chances of both parties gaining seats.
After voting for the alternative alliance, anti-Government voters should then transfer to other potential coalition partners. The Greens are the obvious choice, given that the party has expressed its preference for the alternative FG-Labour alliance.
The Greens stand to pick up transfers from both of the alternative government blocks because they have not ruled out any form of coalition after the election, including coalition with Sinn Féin. The other side of the coin, though, is that by refusing to rule out a coalition deal with Fianna Fáil, the Greens may have lost some potential first preferences to Fine Gael and Labour.
Sinn Féin voters should consider which of the contending blocs they would prefer to see in power and transfer their votes accordingly. The same applies to supporters of smaller parties like the Socialists or Independents.
For all the talk about transfers, the first preference vote is still by far the most important on most ballot papers. In the region of half of all votes cast tomorrow will not pass beyond the number 1, because the candidate who receives them will neither have a quota nor be eliminated.
Where the transfers and tactical voting really come into play is when candidates are eliminated. It generally makes sense for party supporters to give their weaker candidates the number 1 and to transfer on to the stronger.
That can result in unexpected seat gains although it can also backfire and result in senior people losing their seats as Brian Lenihan did in Roscommon in 1973. Broadly speaking, though, the tactic usually works.
Dublin Central provides a classic example of tactical voting in the last election. In a disastrous election for Fine Gael the late Jim Mitchell was eliminated on the fourth count with 4,268 votes.
At that stage Nicky Kehoe of Sinn Féin was 400 votes ahead of the second Fianna Fáil candidate,Dermot Fitzpatrick, and almost all the pundits predicted he would win the seat.
When Mr Mitchell was eliminated 2,842 of his votes transferred to Labour's Joe Costello, ensuring that the Labour TD held his seat. Some 517 of them went to Dr Fitzpatrick and 331 went to Mr Kehoe. That helped to narrow the Sinn Féin candidate's lead but it was on the next count that the decisive transfer took place.
That count involved the distribution of Mr Costello's surplus of 1,063 votes. As Mr Mitchell's votes had brought him over the quota, the actual surplus distributed came from the Fine Gael candidate's bundle of votes and not from the Labour man's original number 1s. Dr Fitzpatrick got 704 votes from the surplus while Mr Keogh got 359. The two-to-one margin in favour of the Fianna Fáil candidate gave him the seat by less than 100 votes.
This was an example of where Fine Gael voters were able to first ensure a Labour ally got the seat when their candidate was knocked out and were also able to decide whether Fianna Fáil or Sinn Féin got the final seat. It was tactical voting at its best.