Labour’s Ed Balls has lost his Morley and Outwood seat to the Conservatives.
The shadow chancellor was beaten by Tory Andrea Jenkyns.
Ms Jenkyns won by just 422 votes, overturning a majority of 1,101 in the 2010 general election.
Mr Balls is Labour’s highest profile casualty in the election.
He said: “The personal disappointment I feel is nothing compared to the sense of sorrow I feel at the result that Labour has achieved in the UK.”
The Conservatives are on course to get a majority overall in the election, with David Cameron expected to form the next government.
The Scottish National Party (SNP) achieved a historic landslide north of the border, winning 56 of 59 seats.