New Labour MP Keir Mather will become the youngest MP in the Commons after overturning a 20,137 majority in the North Yorkshire constituency of Selby & Ainsty.
In a speech after he was declared the winner of the by-election, Mr Mather said he “understood the enormity of what has just happened”.
“We have rewritten the rules on where Labour can win. People have opened their doors to us and embraced our positive vision for the future,” he said.
“The people of Selby & Ainsty have sent a clear message. For too long, Conservatives up here and in Westminster have failed us, and today that changes.”
