A look at five constituencies and what their results might tell us about the changing political landscape.
CLARE
Sinn Féin's Violet Ann Wynn who got 385 votes in the local election just nine months ago, is likely to top the poll with 8,700 votes, according to the final tally.
That would be an incredible swing not just for the candidate but for the party who came close to not running anyone here, until finally adding Wynn at the last minute.
Her victory will most likely come at the expense of Fine Gael. Its party activists in Clare have conceded that they are unlikely to secure two seats with Junior Minister Pat Breen a handful of votes behind his running mate, Joe Carey.
This is one constituency where Fianna Fáil is on course to gain a seat. According to the final tally, first time candidate Cathal Crowe is in second place, behind Sinn Fein.
He is expected to outperform the sitting Fianna Fáil TD Timmy Dooley, who initially seemed to be in the danger zone, but has since recovered significant ground.
MAYO
It was thought earlier that if Rose Conway-Walsh could perform strongly and win a seat here, then the Sinn Féin storm sweeping the country would be stronger than we thought.
Throughout the day the question became not so much if she would win, but whether she would top the poll or come in second place.
Her victory will have to be at the expense of either Fine Gael or Fianna Fáil, both of whom have two seats here.
The casualty will either be one of the most prominent members of the Fianna Fáil front bench, Lisa Chambers, or Fine Gael's Castlebar-side seat held by the former taoiseach Enda Kenny, and now being contested by former county footballer Alan Dillon.
Either would amount to a big disruption of the traditional two-party dominance here.
DUBLIN SOUTH CENTRAL
Fianna Fáil's Catherine Ardagh narrowly missed out on election here in 2016 and went in to this election as one of the party's big hopes.
She is coming in at 11% on the final tally, putting her in fourth place in this four-seat constituency.
But the large surplus of Sinn Féin's Aengus Ó Snodaigh, who at 38% is likely to favour left wing candidates coming in behind Ms Ardagh, mainly Joan Collins, meaning the Fianna Fáil candidate and Fine Gael's Catherine Byrne will be in a fight for the last seat.
Not winning a seat here would be a huge blow to Fianna Fáil's hopes of replenishing its parliamentary party with younger TDs.
But more significantly, it would be emblematic of a collapse for the party in Dublin where there were some hints of a comeback in last year's local elections.
CORK SOUTH CENTRAL
The constituency has long been referred to as the "group of death" because its where the big beasts of politics battle it out.
Going in to this election it had not just one but two or possible three future taoisigh - the Fianna Fáil leader, Micheál Martin, his running mate and potential successor, Michael McGrath, and the Tánaiste, Fine Gael's Simon Coveney.
All three were beaten by Sinn Fein's Donnchadh O Laoghaire, who was elected on the first count with 2,600 votes to spare.
MEATH EAST
Another constituency where its three outgoing TDs have had a big national profile, including Cabinet Minister, Regina Doherty, the Minister for European Affairs Helen McEntee and Fianna Fáil's spokesperson on education, Thomas Byrne.
But Sinn Féin councillor Darren O'Rourke, who has been a vocal critic of Doherty in the local press, is the one who has topped the poll.
This means that there has to be one high profile casualty and it looks like it will be Ms Doherty, who is trailing in fourth place with 10% of the vote share, according to the final tallies.
Her seat loss would become symbolic of just how much this outgoing government is being punished by the electorate.
