Garrett, standing for the Beauties for Britain party, was unable to lure voters managing only 113 votes.

Gordon Brown suffered a humiliating rebuff as the Tories swept to victory in the previously safe Labour seat.

The Conservative, Edward Timpson, demolished a 7,078 Labour majority to capture the Cheshire constituency by 7,860 votes. He won the seat with 20,539 votes, comfortably ahead of Labour’s Tamsin Dunwoody on 12,679 votes. The Liberal Democrat’s Elizabeth Shenton trailed third with 6,040.

The turnout was more than 58.2 per cent, reflecting the huge political and media interest in the contest, regarded as the most important by-election since Labour won power 11 years ago.The anti-Labour swing of about 17 per cent would be enough to give David Cameron victory with a large majority at the next general election. The result will be hailed by the Tories as further evidence that they are winning back support in the industrial north of England. It follows hundreds of gains for the party in this month's council elections and a widening opinion poll lead over the Government.

Labour tried to put the result down to a mid-term protest vote, but the scale of defections from the party will cause alarm in Downing Street, where the Prime Minister is battling to halt a slide in public confidence in his leadership. It could also provoke fresh mutterings among some Labour MPs who fear he is leading them to defeat at the next election.

All three major parties mounted a massive effort in the by-election, which was caused by the death last month of Ms Dunwoody's mother, Gwyneth.

Labour called the contest early in the hope of stopping the Conservatives from building momentum and launched a highly personal campaign in which it branded Mr Timpson a "Tory toff" and portrayed him as a wealthy outsider. The party also hoped the Dunwoody name would help Labour to cling on to the seat.

But it was to no avail as Labour faced a rebellion in the streets of Crewe, largely fuelled by fury over the bungled decision to scrap the 10p minimum rate of income tax. A £2.7bn emergency package designed to compensate most of the losers from the switch was too late to prevent a meltdown in the Labour vote. The party's canvassers also encountered anger over the rising cost of living.

Bolstered by two visits by Mr Cameron to the constituency, the Tories urged voters to use the by-election to "send a message to Mr Brown".

The Crewe and Nantwich constituency had returned a Labour MP since its creation in 1983, while the town of Crewe had been loyal to the party since the Second World War. The constituency had only been 165th on the Tories' list of target seats, requiring an 8.1 per cent swing to fall into their hands.

The victory was its first by-election gain from another party since 1982 when it captured Mitcham and Morden in south London from an SDP MP who had defected from Labour. The fact that it had come in a largely urban northern constituency is a further fillip to the Tories, whose recovery has been patchy across the north of England. They ferried more than 60 Tory MPs to the seat yesterday to try to bring out the vote in areas previously hostile to their message.

Eric Pickles, the party's campaign manager in Crewe, declared victory an hour before it was officially confirmed. He added: "We won the campaign because we engaged on the issues that were important."

Labour strategists will be assessing the scale of discontent within the party over the weekend. They had tried to play down expectations over the result and have already pointed to the fact that the Tories lost two key by-elections shortly before John Major led his party to a surprise victory in 1992.

Mr Brown's options are limited as he has already moved to defuse the 10p row and announced a series of policy initiatives in last week’s draft Queen's Speech. A snap cabinet reshuffle looks unlikely for fear of appearing a panic measure.

However, scope for plotting against him by either Blairite or left-wing critics is limited as MPs left the Commons last night for the Whitsun recess.

Speaking before the result was announced, Hazel Blears, the Communities Secretary, warned the party against responding to defeat with internal feuding.

Ms Blears told BBC1's Question Time: "It might be that the electorate have decided to send us a pretty powerful message but the last thing they want is the Labour Party to turn on itself and be obsessed with our own affairs and not what the public want."

She conceded that the "Tory toff" strategy had backfired, saying: "I think it was a stunt to do the toffs and it failed."

Mr Cameron will seek to capitalise on the victory by calling an early by-election in Henley, the seat due to be vacated by Boris Johnson, the new Mayor of London. 26 June and 3 July are being pencilled in as likely dates for the contest, where the Tories face a strong challenge from Liberal Democrats, but Labour will struggle to retain its deposit.

Results in full

Edward Timpson (C) 20,539; Tamsin Dunwoody (Lab) 12,679; Elizabeth Shenton (LD) 6,040; Mike Nattrass (UKIP) 922; Robert Smith (Green) 359; David Roberts (Eng Dem) 275; The Flying Brick (Loony) 236; Mark Walklate (ND) 217; Paul Thorogood (CTDP) 118; Gemma Garrett (ND) 113.