The political stakes could not be higher as vote goes down to wire
The result of Friday's referendum could have a far deeper impact on our political system than many voters realise.
While the question on the ballot paper will be short and simple, everybody knows the answer will be far more complex and difficult.
And depending on the result, the fallout could be even more significant.
A Yes win will allow the Oireachtas begin what is likely to be a fresh torturous journey towards legislation for abortion.
While Health Minister Simon Harris has given us a general scheme of the bill, the devil will be in the detail.
And there's no guarantee that it will be acceptable to a majority of TDs even if the referendum is passed.
As things stand, it will require Sinn Féin, which supports repeal, to change its overall attitude to abortion.
The party will hold a conference in June to decide whether the 12-week proposal is acceptable to a majority of its membership, including those in Northern Ireland.
History suggests the members rarely go against the leadership - but that has yet to be tested on Mary Lou McDonald or on such a divisive topic.
But the intrigue if there is a No result will be even more pronounced.
It's a very rare day that the leaders of the four main political parties are united on anything. Yet here we are: with 48 hours to polling, they have been brought together by arguably the most contentious issue in Irish society.
Taoiseach Leo Varadkar is leading the charge against enshrining an unborn child's right to life in our Constitution.
The qualified doctor has travelled a long way since 2014 when he would have been a better fit in the No campaign.
Speaking as health minister, he said his duty was to "protect and safeguard" all citizens.
"I consider myself to be pro-life in that I accept that the unborn child is a human life with rights. I cannot, therefore, accept the view that it is a simple matter of choice.
"There are two lives involved in any pregnancy. For that reason, like most people in the country, I do not support abortion on request or on demand," he said.
Yesterday, Mr Varadkar told the Dáil: "The Eighth Amendment is too hard and forces a very hard law on Irish people and Irish women. Let us not forget what the Eighth Amendment says. The Eighth Amendment is eloquent. It says that the right to life of the unborn is equal to that of the mother, so the right to life of a foetus of only a few days' gestation is equal to the right to life of your mother, your sister or your female friends and co-workers."
It is a political shift that will prove badly judged if "most people in the country" have not had the same journey as the Taoiseach over the past four years. The Government will face major questions about how the "once in a generation" campaign was run.
However, if Mr Varadkar and Mr Harris get credited with resolving the abortion question, it could well be the catapult that sends us towards a summer general election.
Then there is Micheál Martin, who is going against the majority of his own party. Just 10 Fianna Fáil TDs are backing the Yes campaign, compared to 33 on the opposing side.
Mr Martin must be hoping he has read the mood of the public better than the rest of his party. If voters side with the status quo, his position will come under scrutiny.
He brought Fianna Fáil back to respectability by reading the public mood during the last general election - but this is an even bigger call.
The Cork South Central TD also sits on the opposite side of the debate from his constituency colleague and finance spokesman Michael McGrath and his new deputy Dara Calleary, who are tipped as future leaders.
As for Mary Lou McDonald, she has used this campaign to launch her own leadership of Sinn Féin. Her image is hanging off posters across the country beside a big 'Yes', leading to accusations that this is more about personality politics than the issue.
Of course, Sinn Féin likes us to forget that its own abortion policy has evolved significantly over recent years.
But Ms McDonald is looking to move a lot further than many of her comrades in Northern Ireland would like.
In fact, the Labour Party is the only one that is being true to its long-held position on this vote.
Referendums are a reflection of the public attitude towards the government of the day - but Friday's vote will be different because all of the political big hitters are on one side.