IN the end it was a virtual landslide and a resounding victory for the Yes side. So how was it done? We look at eight factors that swung the vote in favour of the Lisbon Treaty.

1. The economy stupid

All of the factors listed below were important but none remotely as important as the global economic meltdown of the past 12 months. The Lisbon contest may have been roughly the same, but the pitch on which it was being played was completely different.

The crisis was a massive reminder of the importance of the EU to the small, open Irish economy, a point emphasised by the huge financial backing given by the European Central Bank during the banking crisis.

Many voters wouldn't claim to grasp all the complexities of the economic crisis, but they understood what had happened to Iceland without the protection of the EU. The economic crisis focused minds among those who last time felt Ireland had the luxury of voting No. It allowed the Yes side run a campaign with a heavy 'vote yes to save jobs' and 'we're better with Europe' emphasis. It would be naive to argue that fear didn't play a big role.

It is very difficult to say with certainty what would have happened to Ireland within the EU if there had been a second No vote and Lisbon had fallen, but voters weren't willing to take a chance on that. They were afraid it would impact on foreign direct investment and therefore jobs. They were afraid Ireland would be left without friends and allies in Brussels. They were afraid Ireland would be left behind in a two-tier Europe. And the No side didn't come close to reassuring voters that those fears were groundless – quite possibly because those fears were far from groundless.

2. Guaranteed Irish

The government's securing of guarantees on abortion, neutrality, taxation and the maintenance of our European commissioner effectively pulled the rug from underneath the No side. An opinion poll following the EU council of ministers' meeting last December, when those issues were largely thrashed out, saw a increase of 14 points in the Yes side. It was the beginning of the turn and the Yes side never lost that gain.

The guarantees meant the No side had nothing to get their teeth to. The loss of an automatic commissioner was a key argument in Lisbon 1 but this time the Yes side were able to argue that a Yes vote was the only way to ensure Ireland kept its commissioner.

Focus group and quantitative research carried out by Fianna Fáil after the guarantees were secured showed voters were aware of them, understood them and were more likely to vote Yes because of them. It provided what one government source described as a "letter of transit" for people to move from the No to the Yes side on the basis that their concerns in the first Lisbon referendum had been listened to and addressed.

3.Yes is more

Fifteen months ago, the Yes campaign was a mess. The government delayed over setting a date and was distracted by Bertie Ahern's departure; the main political parties did sweet FA on the ground, squabbled with each other publicly and were led up a series of blind alleys by a No side that set the agenda from day one.

This time it was completely different. From the start the government knew what it was doing. It didn't rush into a referendum. First, it secured the guarantees that allowed it to go to voters and say: 'yes, it's the same treaty but the package is different'.

The Yes campaign was more disciplined and united. All the main political parties were hugely active on the media front and did a lot more work canvassing on the ground.

Taoiseach Brian Cowen also led from the front, visiting constituencies and conducting dozens of media interviews. There was no squabbling between the main political parties this time and the opposition played their part. Helped by the aforementioned economic crisis, the Yes side set the agenda – jobs and foreign investment. On only three occasions did the government engage with the No side: firstly, when Micheál Martin described Cóir as a front for Youth Defence; secondly when Martin hit out at British anti-EU party UKIP's plans to leaflet every home in the country and lastly when Brian Lenihan raised the issue of a hedge fund backing Declan Ganley's campaign. The non-political establishment also played a much bigger role, with civic groups and celebrities such as Robbie Keane and Denis Hickie getting a lot of media focus.

4. No campaign's limits

Let's not beat around the bush, the No campaign was poor. It was made up of disparate groups mostly on the left and the right of the political spectrum hosting sparsely attended press conferences in small rooms. There was none of the va-va-voom provided by the stunning Libertas campaign of last year.

And unlike in the last referendum, it didn't provide solid reasons for voting No (or not voting Yes) and were simply outmuscled by the political establishment and arguments of the business community in favour of a Yes.

The Cóir minimum-wage poster may have got traction, but it and some of that group's other arguments were so discredited that they must have put off other wavering voters. Ultimately though, the anti-Lisbon campaigners simply had no credible response to fears that a No vote would leave Ireland marginalised and friendless in the midst of the worst economic recession in 100 years.

5. 'Cope'-ing with Ganley

Declan Ganley was the star of the anti-Lisbon campaign last time, but that star has been very much on the wane ever since. Fianna Fáil's Pat 'The Cope' Gallagher won't be a name that will be highlighted in many quarters in the coming days as a major factor in the Yes vote, but he has played a crucial role. Fianna Fáil and Gallagher's decision to sacrifice a Dáil seat in Donegal South-West to contest the Euro elections meant Ganley failed to get elected to the European Parliament. The result denied him momentum for Lisbon 2 and when he did finally enter the campaign it was as a failed Euro candidate rather than a MEP, which matters a lot in terms of perception.

Libertas did spend a lot of money in the final days of the campaign, but Ganley had virtually no impact. Unlike 15 months ago, he didn't seem to have a message. With Ganley effectively marked out of it, the No side lacked a convincing figurehead to galvanise support.

6. Doing the business

Corporate Ireland looked on with horror last year as the Yes campaign imploded. This time it was determined that it would not stand idly by. When the likes of Michael O'Leary, the IDA and the chief executives of companies such as Microsoft, Intel and Pfizer come out and say that voting No would put at risk Ireland's strong track record of attracting foreign direct investment, it carries enormous clout.

7. The Sun wot won it

The print media largely backed a Yes vote and that was reflected in newspaper coverage. And unlike last time, the Murdoch newspapers in Ireland – the Sunday Times, News of the World and the Sun – did not come out as strongly in favour of the No side, taking a much more neutral stance.

8. Voter smarts

There were fears that the unpopularity of the government might prompt the electorate to vent their frustration by voting No. Those fears never materialised as voters separated domestic considerations and the issues of Ireland's future in Europe. Efforts to make it a referendum on Brian Cowen failed ­miserably.