Labour has won the City of Chester by-election, retaining the seat and delivering a defeat for Rishi Sunak in his first electoral test as PM.
Samantha Dixon has become the constituency's new MP with a majority of 10,974 votes.
Her party secured more than 61% of the vote with a 14% swing from the Conservatives.
The contest was triggered by the resignation of previous Labour MP Christian Matheson.
He stood down after Parliament's watchdog recommended his suspension for "serious sexual misconduct".
Labour had been fully expected to retain the seat, which it won in 2019 by a majority of 6,164.
In that election, the Conservatives came second, winning 38% of the vote. Labour and the Liberal Democrats secured 50% and 7% respectively.
This time round, Mrs Dixon won with a 61% share, easily defeating Conservative Liz Wardlaw.
Election officials earlier confirmed a turnout of 41%.
In her victory speech Mrs Dixon said the people of Chester "have said unreservedly that Rishi Sunak's Conservatives no longer have a mandate to govern".
She added: "I don't think they believe that the Conservatives have the answers, I think they think it's Labour's turn now."
She then told the BBC: "Voters in Chester really are fed up with the government.
"I think they've turned to Labour values and have put crosses next to my name in significant numbers.
"What I've heard very much on the doorstep is that people really are very worried about their future and the future of their families."
The Conservatives have performed badly in recent by-elections, losing Wakefield to Labour and the historically safe Tory seat of Tiverton and Honiton to the Liberal Democrats.
Those defeats increased political pressure on Boris Johnson, who later resigned as prime minister.
Thursday's by-election was the first to take place since Mr Johnson quit and his successor Liz Truss caused market turbulence with her mini-Budget.
Results in full:
- Samantha Dixon (Labour) 17,309 (61.22%, +11.58%)
- Liz Wardlaw (Conservative) 6,335 (22.40%, -15.93%)
- Rob Herd (Liberal Democrat) 2,368 (8.37%, +1.53%)
- Paul Bowers (Green) 787 (2.78%, +0.15%)
- Jeanie Barton (Reform UK) 773 (2.73%)
- Richard Hewison (Rejoin EU) 277 (0.98%)
- Cain Griffiths (UK Independence Party) 179 (0.63%)
- Howling Laud Hope (Official Monster Raving Loony Party) 156 (0.55%)
- Chris Quartermaine (Freedom Alliance) 91 (0.32%)
Source: BBC
Image: PA Media
