Take a once-poor country with a history of deprivation and colonial subjection. Through husbanding its resources it has managed to make a contribution to United Nations peacekeeping over many years.

A small but respected member of the European Union, it has come in for an economic windfall and is ready to flex its diplomatic muscles by making a bid to serve on the UN Security Council for the third time.

Take a modern Scandinavian state with an enlightened social system, a progressive foreign policy - including active involvement in the Middle East - and deep pockets when it comes to assisting the less fortunate of the world.

Take a middle-ranking European power with an enviable record in UN electoral politics, a strong record of service to NATO and a formidable and well-resourced international network, accustomed to sweeping all before it on the diplomatic front.

In other words, take Ireland, Norway and Italy and the stage is set for one of the closest and most intense battles for Security Council membership in years. It is impossible to persuade even seasoned UN hands to predict the result of the race, which has become the consuming topic of conversation at the organisation's headquarters on Manhattan's East River. The general consensus is that tomorrow's vote is too close to predict.

Five of the 15 Security Council places are up for re-election, but only three are being contested. Ireland, Italy and Norway are competing for two places in the Western European and Other Group, while Mauritius and Sudan fight it out for the African seat. Colombia and Singapore will take the Latin American and Asian seats unopposed.

The Security Council is the UN's holy of holies. It may have a chequered history, and its unwieldy composition might often stand in the way of decisive and effective action, but it is still the forum to which world public opinion invariably turns when all else seems lost.

Ireland is seeking admission to this inner sanctum to serve a two-year term, for the first time since the early 1980s. The aim was laid down in the 1996 White Paper on Foreign Policy, and the campaign began in earnest in late 1998.

Prospects of victory initially looked quite healthy: Norway and Turkey were the other competitors. The complexion of the race changed when Italy entered the lists and Turkey withdrew.

Irish diplomatic feathers were ruffled over the Italian move: if successful, it would take a seat for the second time in a decade. What price now a united bloc vote by the EU countries for one of their own or an appeal in other regions to "vote for the EU candidate"?

Some observers were gloomy. After all, when had the Italians ever lost an election at the UN? And how could Ireland compete with Italy's resources and diplomatic apparatus?

The Irish have tried to turn their weakness into a strength. `Small is beautiful" has been the message. The Big Boys have had their chance, now it's our turn. Although the candidates for the pair of Western European and Other seats have to come from the group, all UN member-states who are reasonably up to date with their dues are entitled to vote. The vote of Tuvalu, a series of atolls in the South Pacific and the UN's newest member, carries the same electoral weight as that of the US or Germany.

Irish hopes are also sustained by the fact that our campaign began early and was planned and implemented with care and precision. A four-member unit, under Assistant Secretary Mary Whelan, was established in Iveagh House, headquarters of the Department of Foreign Affairs; Richard Ryan was dispatched as Ambassador to the UN, where he could deploy the social and diplomatic skills he exercised to such positive effect during the run-up to the Anglo-Irish Agreement in 1985. Politicians were also recruited. The Taoiseach got into the competitive spirit with a round of bilateral meetings during his visit to New York for the UN millennium summit when he also announced a plan to quadruple Irish aid to the developing world.

The Foreign Minister, Brian Cowen, carrying on the work of his predecessor, David Andrews, undertook a demanding schedule of about 60 meetings during his recent trip to the General Assembly. Every junior Minister at every international conference was expected to do his or her share of canvassing. For the first time, Ireland was granted observer status by the Organisation for African Unity, and there are high hopes of support from the potentially-decisive African group.

Cowen also travelled to Washington to appeal to the Secretary of State, Madeleine Albright, and the National Security Adviser, Sandy Berger, for the US vote. Like the other four permanent members of the Security Council - Russia, China, France and Britain - the White House traditionally refrains from indicating its preference, either before or after the ballot. There have been hints recently that China might opt for the Irish.

Although Italy has been generally seen as "the one to beat" there is a view in the Irish camp that success for Norway is by no means guaranteed. Last Wednesday the Norwegians held a reception in the city, hosted by King Harald.

Ireland cannot supply a monarch, but a formidable array of diplomatic talent has been assembled in New York for the Last Big Push. As well as Ambassador Ryan and Ms Whelan, they include the secretary-general of the Department of Foreign Affairs, Padraic McKernan; Envoy to the Holy See, Eamon O Tuathail, who has long experience and good contacts in the Arab world; Anne Anderson, head of our UN Mission in Geneva; and Bernard Davenport, Ambassador to Switzerland, who has a strong background on the Latin American scene and previously served in Buenos Aires.

The contingent also includes the Ambassador to Australia, Richard O'Brien, who toured the South Pacific region with a colleague in a bid to garner votes, in the process uncovering a rich vein of lore about the Irish contribution to the history and genealogy of the South Seas.

Most of the 189 member-states are expected to vote: some whose financial standing with the organisation is poor may still end up on the list of electors.

A two-thirds majority is required for election, which may mean there will be more than one ballot. If written commitments hold good, Ireland will win, but long-time observers warn about the "discount factor". Even written commitments are not always fulfilled: not for nothing has this vote been compared to a Seanad election back home.

It is quite common for ambassadors to the UN to disregard instructions from their home governments and use the secrecy of the ballot to vote whichever way they like, often on the basis of personal relationships with diplomats from the candidate countries or even, at times, on more venal considerations.

The unofficial view among the Iveagh House bureaucracy is that a good campaign has been mounted, and the final result will be very close. It is seen as an uneven contest, given the comparatively lavish resources of Italy and Norway. "If we win it, we will scrape home," an insider said. "If we lose, the principal lesson is that we are just not in the Big Boys' league."