Minister for Local Government Eoghan Murphy, who has responsibility for the referendum on the Eighth Amendment, has said the formal result is unlikely until 6pm because of the high turnout.
He also warned a tight vote in some constituencies could delay the final announcement.
Mr Murphy has described the expected clear outcome of the abortion referendum campaign as “overwhelming”.
The Minister said he did not predict such a clear outcome at all because people were so reluctant, initially at least, to share their views.
“The abortion referendum campaign was a very different campaign to any campaign I’ve ever been involved in,” he said.
Speaking at the RDS on Saturday morning, the Minister said it was a unique campaign “because it was a private decision”, which made it “hard to get a sense on the doors of how people were voting”.
The Minister signed the formal order on March 28th for polling day on May 25th, marking an eight-week campaign.
A Dublin Bay South TD, he said “definitely at the beginning people really didn’t want to get into conversation. They didn’t really want to have a debate on the doorstep.
“A lot of people didn’t want to share their views and normally if they don’t want to share their views on the door you kind of assume that means they’re not voting with you.
“Either they’re not voting for you as a person or they’re not supporting a referendum that you’re supporting.
“So it was hard to get a sense of actually of where things were and that’s why it’s kind of overwhelming to see how strong it was even in my own constituency.”
He said he never had a sense that the referendum would be lost but “maybe not as popular. But there was never a sense of how big the Yes would be”.
As Ireland votes in the referendum on the Eighth Amendment you can follow every twist and turn from early on Friday and across the weekend.
Our live coverage begins at 7am on Friday when polling stations open.
The live blog team will bring you all the latest on turnout and news from voting stations as it emerges. Coverage continues through Friday evening as Ireland awaits the outcome of the referendum, dubbed a “once-in-a-generation” vote on the abortion issue.
From early on Saturday we will provide rolling coverage of the count in each constituency with any early indications of the outcome and the official results as they are announced over the course of the day.
We will also bring you live analysis from our political team in text and on our Inside Politics podcast, as well as reaction from around the world.
Stick with us on Saturday afternoon and through Sunday for a full set of analysis, reaction and comment from our best columnists, correspondents and writers.
On Sunday we will reveal the results of a virtual vote conducted among thousands of members of The Irish Times Abroad Network.
You can stay up to date by downloading our iOS or Android apps or at irishtimes.com. You can also sign up to one of our newsletters, including our Inside Politics digest, which will issue on Saturday and Sunday morning, to keep fully abreast of every development.
Copies of the print edition and ePaper will be available first thing on Monday morning featuring extended coverage of the result and its aftermath.
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In the meantime our continued full coverage of the issues and news from the campaign trail is available on our special referendum site.
If you have a question, our Abortion: The Facts page will have the answer. If you want to know how, where, and when to vote check out our "everything you need to know" article here.
