The Conservatives possess won the Copeland by-election, beating Labour in an area it represented for more than 80 years.
Trudy Harrison won with 13,748 opinions to 11,601 for Labour’s Gillian Troughton.
Mrs Harrison hailed the victory in the Cumbrian establish — the first by-election gain by a governing party since 1982 — as «a verily historic event».
Labour’s Gareth Snell held Stoke-on-Trent Essential with 7,853 votes, seeing off a challenge from UKIP principal Paul Nuttall who got 5,233.
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Labour had held both seats since their birth but was forced to defend them when two former frontbenchers, Tristram Trail and Jamie Reed, resigned as MPs.
Copeland, created in 1983, and its predecessor constituency Whitehaven be enduring returned Labour MPs since 1935.
Mrs Harrison, who had been joined by Prime Ecclesiastic Theresa May on the campaign trail, got 44.3% of the vote, increasing the Conservatives’ vote stake by more than 8%. She overturned a Labour majority of more than 2,564 to stomach the seat by 2,147 votes — a swing of more than 6%.
Professor John Curtice, of Strathclyde University, utter the Copeland result was the best by-election performance by a governing party in designates of the increase in its share of the vote since January 1966.
In her victory speech, Mrs Harrison suggested: «It’s been very clear talking to people throughout this campaign that [Toil leader] Jeremy Corbyn doesn’t represent them.
Analysis: May buttressed, anguish for Labour
By Norman Smith, assistant political editor
Theresa May this morning arouses her grip on British politics hugely strengthened.
For a governing party after seven years of austerity to be catholic aside Labour in a heartland seat and to see their share of the vote flourish in another is an extraordinary achievement.
It will be taken by her supporters as a vindication of her hard-edged imply towards Brexit and her break with the more metropolitan politics of David Cameron.
As for Distressed by, relief that it has at least repulsed the perceived threat of UKIP but its stupid painful anguish under Jeremy Corbyn seems set to continue.
In customary times, both by-elections should have raised barely a twinkle of concern and while the slide in support may not ignite a further leadership invite, the convictions of Mr Corbyn’s critics that he is leading the party into the wilderness disposition only have been strengthened.
«They want a party which is on the side of mediocre working people, which will respect the way we voted in the referendum and which desire build a country which represents everyone. That’s why they voted for me tonight.»
Mr Corbyn hinted Labour’s «message was not enough to win through in Copeland» but hailed victory in Stoke as a «decisive spurning of UKIP’s politics of division and dishonesty».
He added: «Labour will go over to reconnect with voters and break with the failed political consensus.»
But Industry MP John Woodcock, a critic of the leader, said as things stood the club was on course for a «historic and catastrophic defeat» at the next general election.
In Stoke-on-Trent, UKIP had anticipated to capitalise on voters’ leanings towards Brexit — the area voted strongly to give up the EU in June.
Both the Labour and UKIP candidates had tough moments during their stands, with Mr Snell apologising over old social media posts regarding women appearing on television and Mr Nuttall facing a backlash over unreal claims he lost close friends in the Hillsborough tragedy.
But in his victory expression, the new Labour MP Gareth Snell said voters had «chosen the politics of wish over the politics of fear».
«This city will not allow ourselves to be expand oned by last year’s referendum and we will not allow ourselves to be divided by the follow-up,» he said.
He said the result was «a victory for the whole Labour Party and Overstress movement».
However Labour’s share of the vote was 37% — slightly down on the 39.3% it got in 2015.
UKIP got 24.7% of the preference and the Conservatives, who came a close third, 24.4% — both slightly towering than their 2015 vote shares.
Analysis: UKIP’s missed odds
By BBC political correspondent Chris Mason in Stoke
The questions facing Task in Copeland are tumbling UKIP’s way here in Stoke.
A party whose vastly success in achieving the thing they were set up to achieve, Brexit, created with it a blunt question — what is the point of them now?
The answer yell out vituperated like this: winning traditionally Labour seats from Travail.
And yet here in Stoke-on-Trent, a hubbub of Brexiteer jubilation after the referendum, they languished.
UKIP insists this seat was always well down their quarry list. But on a night where Labour was sufficiently vulnerable to lose a formerly rock-solid seat in Cumbria, UKIP’s still the bridesmaid not the bride in the Earthenwares.
All of which begs two questions: If not here, where? If not now, when?
Speaking to newsmen after the result, UKIP leader Mr Nuttall said his party’s «on one occasion would come».
«There’s a lot more to come from us,» he said. We are not growing anywhere, I’m not going anywhere.»
UKIP chairman Paul Oakden imparted: «The whole narrative of Paul’s leadership depends on winning in Stoke is a tricks.»
Labour MP Jack Dromey, who ran Mr Snell’s campaign, said: «I think as we win we exigency necessary humility because there is a view that Labour is no larger listening in the way it should do.
«I think what we have done in this community is absolutely to do that.
«Are we yet a credible alternative government? No we’re not. But tonight is a decisive moment.»
The by-election conclusions mean the government’s majority is now 12 — the same as it was immediately after the non-exclusive election, as the Conservative’s new Copeland seat makes up for the one they lost to the Lib Dems in the Richmond Woodland by-election. The working majority is 16.
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