Polling stations around the State have closed after 15 hours of voting in the Presidential election, a by-election in the Dublin West constituency and referendums on judicial pay and Oireachtas investigations.

Turnout looks like being higher than the 47% recorded in the last Presidential poll 14 years ago, but considerably lower than the 70% who voted in February's General Election.

Ballot boxes will be opened tomorrow morning in each of the constituency count centres, with the Presidential ballot papers being separated from those for the referendums.

Counting will then begin on the Presidential election, and in Dublin West on the by-election there.

A first count is not expected until early evening. The final result could come early on Saturday morning, or the count could be adjourned if it looks like going on too late.

Once the Presidency is decided, counting of votes in the two referendums will commence.

Just over 3.1m people - every Irish citizen over the age of 18 who is included on the Register of Electors or the Supplementary Register - were entitled to vote.

Voters in Dublin West had a fourth ballot paper for the by-election to fill the Dáil seat left vacant by the death of Brian Lenihan.

President Mary McAleese voted in the Phoenix Park this morning accompanied by her husband Senator Martin McAleese.

Michael D Higgins cast his vote at Bushy Park National School in Galway, while Seán Gallagher voted in the National School in Blackrock, Co Louth.

Gay Mitchell voted at Kildare Place Primary School in Rathmines and Dana Rosemary Scallon cast her vote at Carnmore National School in Claregalway.

David Norris voted at Marlborough Street polling station, Mary Davis voted in the Burrow School in Sutton and Martin McGuinness - who is not eligible to vote in the election - joined Pearse Doherty at the polling station in Bunbeg in Co Donegal.