The Alliance deputy leader Naomi Long caused the shock of the Westminster election in Northern Ireland taking Peter Robinson's seat in East Belfast, and raising questions about his position as DUP leader and First Minister.
The results of the polls in all but one of the North's 18 constituencies have been so far been decided.
A third recount began in the Fermanagh/South Tyrone constituency at 11am. Second tallies had the unionist unity candidate Rodney Connor trailing Sinn Féin's agriculture ninister Michelle Gildernew by just two votes. She eventually retained her seat by just four votes.
The final results from the North's 18 consituencies are: DUP - 8 seats; Sinn Féin - 5; SDLP - 3; Alliance - 1, independent unionist (Lady Sylvia Hermon) - 1 seat.
In the 2005 Westminster election the DUP won nine seats, Sinn Féin five, the SDLP three and the Ulster Unionist Party took one seat, although Lady Hermon recently resigned from the UUP because of the link-up with the Tories.
Belfast lord mayor Ms Long was declared elected for East Belfast just before 1am this morning, taking 12,839 votes against 11,306 votes for Mr Robinson. Former Irish rugby international Trevor Ringland was third, polling 7,305.
Ms Long won by 1,533 votes to make her the first Alliance member to be elected to the House of Commons.
Questions have been raised about Sir Reg Empey's leadership of the Ulster Unionist Party and his decision to support an alliance with the Conservatives after he failed to take the seat of the DUP's Rev William McCrea in South Antrim.
The Traditional Unionist Voice fared poorly elsewhere but the party drew solace from the 1,850 votes that David Vance of the TUV took in East Belfast which may have cost Mr Robinson his seat. In other circumstances these votes would have been expected to go to Mr Robinson.
Mr Robinson had a majority of almost 6,000 in the last election but it was clear early this morning that an extraordinary result was possible, and so it transpired. Reporters noted the bundles of votes and the indications were that Ms Long's were higher than the First Minister's.
He was under pressure from the outset of the campaign over "Irisgate" and reports of land deals, but the fact that he lost the seat which he held since 1979 was a sensation.
Mr Robinson graciously acknowledged his defeat shortly before 1am. He "congratulated Naomi for a successful campaign" and said he was "honoured" to have served the constituency.
Mr Robinson indicated he would not stand down from politics and that the DUP would continue to look positively at the future of Northern Ireland. "I have a job to do and I have a job to complete with my mandate in the Assembly. I will continue to carry out that important work. I think it is vital for the sake of Northern Ireland that we continue the momentum of moving forward," he said.
"No matter in what role I may be able to play my part I will always do my best to get the best deal for the people of Northern Ireland," added Mr Robinson.
Richard Bullock, a DUP adviser, told RTÉ: "There's no doubt that Peter's defeat in east Belfast was a severe blow for the party". He added that the DUP had a successful election elsewhere in the UK region.
Deputy DUP leader Nigel Dodds said Conservative leader David Cameron may seek to reach an agreement with his party.
The results also left the leadership of the UUP under threat after the gamble of East Belfast MLA Sir Reg moving to South Antrim failed with outgoing MP, the Rev William McCrea winning, albeit with a reduced majority.
The fact that Lady Hermon won North Down in a "landslide" has put further pressure on his leadership. She resigned from the UUP because Sir Reg signed up to the link-up with the Tories through the Ulster Conservatives and Unionists-New Force (UCUNF).
The results could also create the ground for the realignment of unionism with the DUP's Arlene Foster, who briefly stood in for Mr Robinson earlier this year as First Minister, as a possible uniting force.
The SDLP performed well holding its three seats with new leader Margaret Ritchie, with the assistance of some unionist tactical voting, more than 8,000 votes ahead of Caitriona Ruane of Sinn Féin in South Down.
A possible republican dissident car bomb left near the Templemore Sports Centre in Derry last night forced the PSNI to order counters, politicians, staff, journalists and other observers to leave the centre for a period.
As results started to come in early this morning from the other seven count centres, the two Derry counts at the sports complex had to be suspended for a period because of the alert.
When the counts resumed former SDLP leader Mark Durkan won Foyle with a majority of almost 5,000 from Sinn Féin's Martina Anderson. DUP's Gregory Campbell became the last man to win a seat overnight when he held East Derry from Sinn Féin's Cathal O hOisin.
The first MP officially returned was Sinn Féin's Pat Doherty in West Tyrone, whose election was announced at 12.37am.
Minutes later, the DUP's Ian Paisley junior in North Antrim was confirmed as winning easily from Jim Allister of the Traditional Unionist Voice. Mr Paisley's father and former DUP leader, the Rev Ian Paisley and his wife Baroness Eileen Paisley arrived at the count centre in Ballymena around midnight. Dr Paisley said Mr Allister and the TUV were now "written off".
Sinn Féin leader Gerry Adams won easily in West Belfast with 22,840 votes although his vote was down from the 24,348 he won in 2005. Deputy First Minister Martin McGuinness won equally comfortably in Mid-Ulster, as did Sinn Féin Minister Conor Murphy in Newry and Armagh.
DUP deputy leader Nigel Dodds held North Belfast but Sinn Féin's Gerry Kelly closed the gap to just over 2,000 votes from 5,000 votes in 2005. In Lagan Valley the DUP's Jeffrey Donaldson, who had faced controversy over his Westminster expenses, won comfortably.
The SDLP's outgoing MP Dr Alasdair McDonnell comfortably won South Belfast against the opposition of the DUP's Jimmy Spratt and Paula Bradshaw of UCUNF.
David Simpson of the DUP also held his seat in the neighbouring constituency of Upper Bann. DUP finance Minister Sammy Wilson won by almost 7,000 votes from UCUNF candidate Rodney McCune.
Jim Shannon of the DUP beat former UTV news anchorman Mike Nesbitt of UCUNF in Strangford, where the former MP was Iris Robinson.