Empey signalled he will consider his future with party officials over the weekend, while the Democratic Unionists face questions over whether they will stick with their scandal-hit leader.
Meanwhile, there was a dramatic win for Sinn Féin who held the border constituency of Fermanagh -South Tyrone by only four votes, helping the party emerge with the largest share of support in Northern Ireland, which possibly puts it on course to top the poll in next year’s Assembly election.
The Ulster Unionists have been left without an MP for the first time in the party’s history, despite its much hyped alliance with the Conservatives, and while the DUP held eight of its nine seats, the shock defeat of its leader by the Alliance Party’s Naomi Long in East Belfast has rocked the main unionist party.
But senior DUP representative Arlene Foster, who stepped in as First Minister when her leader temporarily withdrew from the post after a sex scandal engulfed his wife, yesterday backed Robinson.
“What happened last night was a very firm reaction I think, right across Northern Ireland, to Peter’s policies, to his strategies, for the way forward for Northern Ireland,” she said.
“I think there was a wall of media attention to Peter over this last six months so it is not surprising what has happened.
“But we all of course in the party are deeply disappointed for him after the leadership he has given to Northern Ireland... he will continue to lead us from the front. We know that his strategy has paid off.”
She said the DUP’s critics in the hard-line Traditional Unionist Voice (TUV) had lost support and had notably failed to seize the DUP stronghold of North Antrim where Ian Paisley Jnr retained the seat held for decades by his famous father.
But Robinson sensationally lost his east Belfast seat in the biggest upset in Northern Ireland’s modern political history.
The shock waves from Long’s stunning victory for the Alliance Party left the DUP reeling.
The seismic result comes in the wake of a series of damaging revelations about both the DUP leader and his wife Iris, who dramatically quit politics in disgrace over allegations about her financial involvement with her teenage lover.
Robinson, 61, defiantly clung to power in the wake of the scandals, insisting he had done nothing wrong, but the loss of a seat he has held since 1979 will cast doubt on whether he can survive as First Minister and leader of his party.
In the wake of the result, which saw his 6,000 majority turned into a 1,500 vote reverse, he vowed to fight on.
“I have a job to complete with my mandate at the Assembly and I will continue to carry out that important work,” he said.
A visibly emotional Long, whose win secured the cross-community Alliance party’s first ever Westminster seat, thanked the voters for backing her. “I went to the electorate with a track record of hard work, with a passion for east Belfast, where I have lived my whole life, and with a dedication to serve them in an open and transparent way and give them my best and to build a better future for everyone in east Belfast,” said Long, who trailed in third in the 2005 poll, more than 11,000 votes behind Robinson.
Robinson has faced a series of allegations in the last year, consistently denying wrong-doing. He was forced to temporarily stand down as First Minister in January to address claims that he knew his wife had failed to declare her role in obtaining £50,000 (€58,000) for her lover’s business but did not report her to the authorities.
The DUP leader returned to office after claiming an independent legal adviser cleared him of wrong-doing. His wife, who tried to commit suicide after her husband discovered her affair, is currently in acute psychiatric care.
The DUP has now won the election to replace the seat vacated on Castlereagh Borough Council by Iris Robinson when she left political life.
While DUP sources rallied to Robinson’s defence, the UUP leader seemed under greatest immediate threat after he failed in his bid to wrest the South Antrim seat from the Democratic Unionists.
The UUP lost its sole MP, Sylvia Hermon, who refused to endorse the party’s political link with the Conservatives. She dramatically held her North Down seat, standing as an independent.
Despite the high profile backing of Conservative leader David Cameron, none of the 17 candidates standing on the joint Tory /UUP ticket was elected.