The Liberal Democrats have unseated Zac Goldsmith of his former parliamentary constituency after he quit the Conservatives over the government’s decision to expand Heathrow Airport.
Sarah Olney’s victory in Richmond, southwest London - overturned the Conservatives’ 23,000 majority from 2015 - illustrating the deep divisions running through a country that voted 52-48 percent to leave the EU.
Her victory was seen as a rejection of a “hard Brexit” that would pull the country out of the single market.
It also reduces Theresa May’s already slim majority in parliament, which might have to approve her decision to trigger the formal process of withdrawing from the bloc.
The affluent Richmond Park and North Kingston area had backed the Remain camp in June’s referendum on EU membership.
Olney, who had campaigned for the parliamentary seat on a promise to vote against triggering the withdrawal talks, said its residents had sent “a shockwave” through the Brexit process.
“Our message is clear: we do not want a hard Brexit; we do not want to be pulled out of the single market; and we will not let intolerance, division and fear win,” she said in a speech after her victory was announced.
She beat Goldsmith with 20,510 votes to his 18,638 after he ran as an independent candidate after quitting the Conservative party.
Goldsmith sparked controversy during his London mayoral campaign and was accused of racism when he claimed Sadiq Khan had links with Muslim hardliners.
All the main candidates in Richmond opposed Heathrow expansion, however, and the Liberal Democrats turned the by-election into a vote on the terms of Brexit.
Goldsmith, the son of a billionaire financier, was a longstanding supporter of Brexit.
May’s Conservatives, which did not field a candidate to oppose Goldsmith, said the result did not change anything in terms of Britain’s Brexit strategy and invoking Article 50 of the EU’s Lisbon Treaty to begin the withdrawal process.
“The government remains committed to leaving the European Union and triggering Article 50 by the end of March next year,” a Conservative spokesman said on Friday.
The Liberal Democrats, the junior partner in a coalition government with the Conservatives for five years before they were crushed at the 2015 general election, have said they want a second referendum on the terms of the Brexit deal.
“What this by-election shows is that it’s a warning to all political parties as to potentially how disruptive this Brexit process is going to be for the regular practice of party politics,” polling expert John Curtice told the BBC.
“It is the impact of Brexit on our domestic party politics that is why this by-election matters.”
The Liberal Democrats held Richmond Park for 13 years until 2010. Their victory follows a strong second-place result for the party in an October by-election for a constituency vacated by former prime minister David Cameron.
May’s Conservatives face another by-election on Dec. 8, after one of their MPs, Stephen Phillips, resigned in November citing “irreconcilable policy differences” with the government.