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Resounding victory for Andy McDonald for Labour in Middlesbrough. #votelabour— @PhilWilsonMP 30 November 2012
Congratulations to Andy Mcdonald MP.He will be a strong voice for Middlesbrough in Parliament.— @KevanJonesMP 30 November 2012
declaration time. http://t.co/Kj97sjXu— @graemeecho 30 November 2012
Both coalition parties preserved their deposits, but Liberal Democrat George Selmer took only 1,672 votes and Conservative Ben Houchen 1,063 - just three votes ahead of the candidate standing for the Peace Party.
Labour's majority of 48.68% was well up on the 26% margin recorded in 2010 by Sir Stuart Bell.
In his victory speech, new Middlesbrough MP Andy McDonald said: "I feel so proud to represent the town I was born and brought up in.
"I promise to fight for all of the people who live here. The people of the town have spoken.
"Tonight we have a new voice in Westminster and I shall make it loud and clear."
Labour win Middlesbrough with UKIP in second and the Liberal Democrats in third.
UKIP are reported to have come second in Middlesbrough, although the official result is yet to be announced.
A result in Middlesbrough is thought to be imminent.
The Liberal Democrat candidate in Rotherham, Michael Beckett, from Norton in North Yorkshire, came eighth, winning 451 votes.
Labour's Sarah Champion has been elected as MP for Rotherham. The UKIP candidate Jane Collins came second.
The Press Association is reporting that Labour is hopeful of increasing its 46 per cent share of the vote from the 2010 election, while UKIP could sneak into second place.
Quite a few spoiled votes in #Middlesbrough with people placing two crosses on the ballot paper. Hangover from the pcc election.— @tommywilkinson 30 November 2012
RT @BBCRichardMoss So much for a half past midnight declaration in Middlesbrough. Counting still continuing though it is winding down.— @alistairmiskin 30 November 2012
the count at the Middlesbrough by-election could be finished in the next 20 minutes. It's looking like a Labour hold.— @graemeecho 30 November 2012
The turn out is less than half the number who voted in the 2010 general election when Sir Stuart with an 8,689 majority.
RT @StanCollymore: 26 per cent turnout for Middlesbrough bi election. The continuing worrying apathy towards politics in the UK.— @rickyrinder3 30 November 2012
Turn out is estimated to be 25 per cent for the by-election.
The count could be finished by 12.30am but it could take a little longer than anticipated.
the view from Southland Centre where the by-election count for Middlesbrough. http://t.co/WlGcmshF— @graemeecho 29 November 2012
I'm now told the turnout is 26% in Middlesbrough with around 16,900 votes cast.— @BBCRichardMoss 29 November 2012
RT @bbcdmacmillan: Turnout in the #Middlesbrough by-election is reported to be 25%. Still to have that confirmed though.— @alistairmiskin 29 November 2012
The atmophere where the count is taking place is a little bit subdued with not many people on the floor.
Labour are confident of holding onto the seat while the Ukip candidate believes he is in with a chance of taking second place in the polls.
UKIP leader Nigel Farage has told BBC Five Live that he expects to come a good second in the Middlesbrough by-election.— @BBCRichardMoss 29 November 2012
RT @bbcdmacmillan: The last Middlesbrough by-election was in 1878, won by railway pioneer Isaac Wilson. He now has a pub named after him under the A66.— @BBCMarkDenten 29 November 2012
Polls have also taken place today in Croydon North and Rotherham. Labour are odds-on at the bookmakers to retain all three seats.
The count underway gets underway...
Sir Stuart had a 8,689 majority for the Labour party and Andy McDonald is the hot favourite to win the seat for the party.
The first of the candidates are starting to arrive at the Southland Centre for the count.
The first of ballot boxes opened and the count is due to start.
The first ballot boxes are waiting to be opened as volunteers get ready to start the count to discover who will replace Sir Stuart Bell as Middlesbrough MP.
The polling booths for the Middlesbrough by-election have now closed. Awaiting the first of the ballot boxes to arrive at the Southland Centre.
I'll be sending updates through the night from the count at the Southland Centre and the result as it's announced.
There is less than six hours left for people to vote in the Middlesbrough by-election. Counting is expected to start at 10.30pm.