Labour candidate Andy Sawford has been elected as the new Corby and East Northants MP.
Mr Sawford reclaimed the seat for Labour from the Conservatives at the by-election called after the resignation of Louise Mensch in the summer.
Mr Sawford polled more than 17,267 votes, with Conservative candidate Christine Emmett polling 9,476.
Mr Sawford said: “Middle England has sent a very clear message to David Cameron.”
UKIP candidate Margot Paker was placed third of the 14 candidates with 5,108 votes, pushing the Liberal Democrats and their candidate Jill Hope into fourth with 1,770 votes.
The Liberal Democrats called for two recounts in a bid to save their deposit, which they failed to achieve.
The 45 per cent turnout at the election is well below the turnout at the General Election in 2010 which saw Mrs Mensch defeat former MP Phil Hope by less than 2,000 votes.
After being announced as winner, Mr Sawford said the result “showed Ed Miliband was changing the Labour Party”, and that the party was gaining the trust of the people.
He said: “Today middle England has spoken and they have sent a clear message to David Cameron. Holding this seat was crucial to David Cameron’s credibility.”
Almost every major political figure in the country has visited the constituency during the election campaign.
They included Prime Minister David Cameron, Labour leader Ed Miliband, the Liberal Democrats leader Nick Clegg and UKIP leader Nigel Farage.
During his campaign, Mr Sawford stressed he was a local man for local people and pledged to fight for jobs, local investment and to protect services at Kettering Hospital.
The nation’s eyes have been on the constituency since Mrs Mensch gave up her seat to move to New York with her children to be with her husband Peter.
Mrs Mensch took to Twitter as the polls closed on Thursday night to tell followers that she would take responsibility if the Tory candidate failed to retain the seat.
She tweeted: “Election result will not be a verdict on either Christine, or the Conservatives, but only on the decision I took to step down mid-term.”
Mrs Mensch added: “Though I had to resign to unite our family, there was large and entirely understandable local anger. I wish I had been able to see out my term.”
The Labour victory will be viewed as a verdict on the Coalition Government’s austerity measures and its handling of the economy.
The Labour leader Ed Miliband first visited the constituency on August 9 to launch Mr Sawford’s bid for election, and the campaign took one final twist when the Conservative MP for Daventry Chris Heaton-Harris, who was Christine Emmett’s campaign manager, was forced to issue a statement after seeming to back a rival.
Mr Heaton-Harris, a well-known opponent of wind farms, was filmed apparently admitting he had encouraged his friend James Delingpole, a Daily Telegraph writer, to put his name forward as part of a “strategy” against onshore wind farms.
On a lighter note, Mr Mozzarella, of the Don’t Cook Party, was possibly the real star of the election, winning cross party support. He arrived in Coronation Park in Corby on the Saturday before the election by jet-propelled backpack.
FULL REACTION AND INTERVIEWS WITH THE WINNER AND LOSERS TO COME