As results of the early counts come in from the 32 count centres, a number of trends and results are emerging from the 40 constituencies.
Conor McMorrow of RTÉ's political staff has identified "20 things we've learned" so far.
#1 The Government parties are going to lose at least 40 seats in this election. It appears that Fine Gael is going to lose 20 seats.
It had 67 seats on the day the Dáil was dissolved and it now appears it will come back with a seat range in the mid-40s.
#2 The Labour Party came into this election with 33 candidates and it now looks like it will come back with a seat tally in the single digits.
#3 Minister for Communications Alex White is the first big name casualty of a terrible day for Labour.
#4 A number of other "big names" are in danger of losing their seats.
Among them are Fine Gael deputy leader and Minister for Children James Reilly; Fine Gael TD and Diaspora Minister Jimmy Deenihan; Minister for Housing Paudie Coffey; Labour leader and Tánaiste Joan Burton; Labour TD and Minister for Education Jan O'Sullivan; Labour TD, Deputy Government Chief Whip and Labour TD Emmet Stagg and Labour TD Willie Penrose.
Renua party leader Lucinda Creighton is in a dogfight to keep her seat.
#5 Independent Alliance TD Shane Ross in Dún Laoghaire was the first TD elected today.
#6 Fianna Fáil leader Micheál Martin has said his party will be nominating him for Taoiseach on 10 March.
Speaking on RTÉ Radio One, he said the formation of a government has to be around the principles of change called for by the people, adding that it was not just a matter for the two big parties.
He said he has not given the idea of "joint Taoiseach" any thought at all.
#7 Among the unexpected results today appears to be Fianna Fáil winning three out of five seats in Carlow-Kilkenny.
This marks a complete reversal on the 2011 result where Fianna Fáil won just one seat and Fine Gael won three of the five seats.
#8 Former Fianna Fáil cabinet minister Mary Hanafin has this evening conceded that she will not win back her seat in Dún Laoghaire.
She says AAA-PBP Richard Boyd Barrett will beat her to the last seat.
#9 In a bad day for Fine Gael nationally, the party's vote management in the Dún Laoghaire constituency means both Mary Mitchell O'Connor and Maria Bailey will get elected.
#10 Green Party deputy leader and Dublin-Rathdown candidate Catherine Martin looks set to win back a seat for the party that was decimated in 2011.
#11 Fianna Fáil candidate Mary Butler has topped the poll in Waterford and she was elected shortly after 5pm. She is the first new woman TD elected today.
#12 Róisín Shortall of the Social Democrats has been elected on the first court in Dublin North-West. Another of the three Social Democrat party leaders, Catherine Murphy, was also elected in Kildare North shortly before tea time.
#13 Michael McGrath and Micheál Martin of Fianna Fáil were elected in Cork South-Central shortly before 6pm.
Fine Gael's Simon Coveney will take the third seat and his party colleague Jerry Buttimer faces an uphill battle with Sinn Féin's Donnchadh Ó Laoghaire for the final seat.
#14 John Perry's director of elections says the Government got the Fine Gael "Keep the Recovery Going" message wrong. Thomas Walsh says it was "a message of arrogance."
He told RTÉ News that Mr Perry, who has served for 19 years, will not be a TD in the next Dáil. Mr Perry received 7% of the vote after going to the High Court to be included on the ticket after he failed to be selected at convention.
#15 Former Labour TD Colm Keaveney, now a Fianna Fáil candidate in Galway East, has been excluded. His running mate Anne Rabbitte is expected to be elected.
#16 Senior Fine Gael Figure Simon Coveney said this evening that this has been a very disappointing outcome for the party. But he cautioned it was too early to talk about coalition options.
#17 Sinn Féin will increase its presence in Leinster House with a number of new TDs getting elected on the party ticket. The first of these new Sinn Féin TDs to be elected was Eoin Ó Broin in Dublin Mid-West.
#18 Sean Canney of the Independent Alliance is on course to be returned in Galway East in what has been a good day for independents.
#19 Gains for the AAA-PBP are also likely with Gino Kenny in Dublin Midwest and Mick Barry in Cork North-Central well place to be elected.
#20 In a sign of how bad things are for Labour, there are now no Labour TDs in Cork City, once a Labour stronghold.
By Conor McMorrow, RTÉ Political Staff
