Colum Eastwood, wife Rachel and Councillor Brian Tierney at the election count in Magherafelt.
Margin of Eastwood victory outstrips John Hume largest majority of 32 years ago
The SDLP has regained the Foyle Westminster seat with a majority in excess of 17,000 votes.
In a remarkable victory leader Colum Eastwood amassed a total of 26,881 votes that equated to 56.7% of the overall poll in the constituency.
The margin of the victory represents not only the largest majority ever in the Foyle constituency but eclipses the biggest previous majority won in 1987 by the SDLP's John Hume by some distance.
Mr Hume first won the the seat after it's creation in 1983 and won with a majority of 8,148. But the former SDLP leader increased that majority to 13,860 four years later. Colum Eastwood's win on Thursday surpassed that by 3,310 votes.
Outgoing Sinn Fein MP Elisha McCallion polled 20.5% of the vote (9,711) but the SDLP majority was 17,170.
The DUP candidate Gary Middleton was down on his performance of 2017. He gained 4,773 or just of 10% of the overall vote, but two years ago he received 7,398 votes (16.1%).
Aontú's Anne McCloskey registered 2,032 (4.29%) and was the fourth highest polling candidate.
Meanwhile, People Before Profit's Shaun Harkin was also down on his tally from June 2017 and registered 1,332 (2.81 per cent).
The Alliance Party's Rachel Ferguson who received 1,267 votes (2.67%) and Darren Guy of the Ulster Unionist Party (UUP) who won 1,088 votes (2.3 per cent) failed to make any real impact.
Of a total electorate of 74,346 just 47,370 (63.72%) turned out which was down in percentage terms on 2017 with Thursday's bleak weather conditions perhaps a factor in that.
After his victory Mr Eastwood thanked all of his opponents for their campaigns and said: "I've been both sides of election counts. I've fought elections ans lost elections. I learned not to take winning or losing too seriously and there's always another day.
"I want to especially thank the people of Derry. I think they have sent a very clear message. In fact I think they've roared that message to all of us in politics today."
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