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Opposition Labour Party overturns two large majorities
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Defeats piles pressure on PM Sunak
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Polls seen as test of public support before national election
(Adds Starmer comment in paragraphs 4-5, Conservative reaction in paragraphs 8, 10-11)
By Andrew MacAskill and Elizabeth Piper
LONDON, Oct 20 (Reuters) - Britain's Labour Party dealt a crushing blow to Prime Minister Rishi Sunak's Conservatives on Friday, winning two previously safe parliamentary seats in victories leader Keir Starmer said showed voters wanted change at the next national election.
The double defeat showed a dramatic slump in support for the governing Conservatives, who have won the last four national votes, and suggests Labour is on course to win power for the first time since 2010 at an election expected next year.
While so-called by-elections are often lost by the governing party, the scale of the defeat in two parliamentary seats the Conservatives have held for years piles pressure on Sunak, who took over almost a year ago after the governing party became embroiled in scandals and chaos under previous leaders.
Starmer
, who has moved his Labour Party closer to the centre, said the two votes showed "Labour is back in the service of working people and redrawing the political map".
"Winning in these Tory (Conservative) strongholds shows that people overwhelmingly want change and they're ready to put their faith in our changed Labour Party to deliver it," he said in a statement.
Labour won the seat of Mid-Bedfordshire, an area about 50 miles (80 km) north of London, overturning a majority of almost 25,000, making it the biggest deficit the party has overcome in a by-election since 1945.
Labour also overturned a large majority in another former Conservative stronghold, Tamworth, a largely rural constituency in central England, with the party enjoying the second-highest swing from Conservatives since World War Two.
Many Conservatives had already resigned themselves to losing the two votes, blaming the former lawmakers for handing victory to Labour by the troubled circumstances of their resignations. But several said Sunak still had time to try to claw back the substantial lead Starmer's party enjoys in the opinion polls, but would have to make a bolder offer to voters.
The Conservative party has only won one of the last 12 by-elections in this parliament, with half of the contests caused by resignations of politicians for misconduct.
Greg Hands, the Conservatives' campaign chief, pointed to the low turnout, saying the Conservatives had to find a way to get their traditional supporters out to vote.