Winners

David Cameron

No general election result in recent history has done more to transform a prime minister’s reputation. Before 7 May 2015, David Cameron was derided by opponents as the man who failed to win against Gordon Brown. Afterwards, he stood triumphant, the first Conservative leader to achieve a majority for 23 years. The pundits, pollsters and MPs who had pre-written his political obituary were silenced. His opponents - Ed Miliband, Nick Clegg, Nigel Farage - were scattered to the wind.

Cameron’s victory, so unexpected he had not even prepared a speech for the occasion, meant he became the first prime minister since Lord Palmerston in 1857 to increase both his party’s share of the vote and seats. His decision to launch on all-out assault on his coalition partners, the Liberal Democrats, (the “black widow strategy”) was vindicated as the Tories captured 27 of their seats. That the fallen included Cameron’s cabinet nemesis, Vince Cable and, from Labour, Ed Balls (“the most annoying person in British politics”), made it a surreally perfect night for the PM.

This was a victory that was achieved because of Cameron, rather than in spite of him. The Tories framed the election as a referendum on the next prime minister and profited from his superior ratings.

Cameron’s second term at No10 will be defined by two decisions he took before the election: to hold an in/out EU referendum and to resign before 2020. The former, which Cameron conceded against his will, is likely to be held in 2016. A vote to leave the EU would almost certainly force his departure, little more than a year after his victory.

Should the UK opt to remain, Cameron’s legacy will be further enhanced, though his premiership still risks being cut short. But by resolving not to fight another election he has given himself a chance of achieving what no Tory prime minister has since Stanley Baldwin: leaving office at a time of his choosing.

Jeremy Corbyn

When Jeremy Corbyn made the Labour leadership ballot with two minutes to spare, most, including himself, believed he would do well to avoid finishing last. What resulted was the most extraordinary victory in British political history.

Corbyn became the first person ever to become leader of the opposition having never served on the frontbench and the most left-wing leader in Labour’s 116-year history. His landslide victory (59.5 per cent of the vote) was even greater that of Tony Blair in 1994 (57 per cent).

After winning with the support of just 14 MPs, some predicted that he would be ousted “before Christmas” and would be unable to form a full frontbench team. Twelve former shadow cabinet members, including Yvette Cooper, Chuka Umunna and Chris Leslie, chose not to serve under him but Corbyn persuaded more than 100 of his colleagues to do so.

His opening months have rarely been without incident. Corbyn exposed himself to attack and intensified Labour’s divisions by failing to sing the national anthem, opposing shoot-to-kill (forcing a clarification), making Trident opponent Ken Livingstone co-chair of the party’s defence review and attending Stop The War’s annual fundraiser.

But he reached his 100th day in the job in a stronger position than ever. Labour’s comfortable victory in the Oldham West by-election ended talk of his early removal, his opposition to air strikes in Syria was backed by a majority of members, MPs and shadow cabinet ministers and his popularity among activists is undiminished. More than 100,000 members have joined since Corbyn’s election, while around 30,000 have departed, moving Labour’s centre of gravity further leftwards.

The party’s poll ratings have flatlined since the election and Corbyn’s are among the lowest of any opposition leader in recent history. But his standing among members is unlikely to be affected. As long as Corbyn fulfils his mandate to oppose austerity, to oppose military intervention and to implement party reform, he will retain their support and be formidably difficult for any challenger to remove.

Nicola Sturgeon

After seamlessly succeeding Alex Salmond as Scottish First Minister in 2014, Nicola Sturgeon took the SNP to stunning new heights. The party won 56 of Scotland’s 59 seats at the general election and 50 per cent of the vote, a victory so resounding that the initial exit poll was not believed by strategists.

This result owed much to Sturgeon (“the most dangerous woman in Britain” as the Daily Mail had it) whose formidable debating skills, social democratic politics and unflashy style allowed her to broaden the SNP’s electoral coalition even further. It was testament to the leader’s appeal that a significant number of English residents longed for the chance to vote for her.

Though the election result denied the SNP the chance to exert influence over a Labour minority government, the Conservatives’ victory meant they could maintain their insurgent status. Should the UK choose to leave the EU in the forthcoming referendum, while Scotland votes to remain, it could also provide justification for a second independence plebiscite.

Not all went plan for the SNP. Seven months after the election, two of its MPs - Natalie McGarry and Michelle Thomson - had the whip withdrawn after becoming the subject of police investigations. The price of oil, Scotland’s most valuable resource, fell to an 11-year low. And the Forth Road Bridge was closed after essential maintenance work was delayed.

But the party’s stratospheric popularity continued regardless. Such is the SNP’s polling strength that it could deprive Labour of every one of its constituency seats in next May’s parliamentary election. As Sturgeon eyes an unprecedented mandate, her opponents privately confess that they know no means of halting her advance.

Sadiq Khan

When Sadiq Khan launched his bid to become Labour’s London mayoral candidate, few identified him as the likely winner. It was Tessa Jowell, renowned for her Olympics role, who was the bookies’ and the pundits’ favourite. But Khan’s victory over her was emphatic, winning among every section of the selectorate (party members, registered supporters, affiliated supporters) and achieving 58.9 per cent of the vote. The Tooting MP’s nomination of Jeremy Corbyn, opposition to the Iraq war and opposition to the welfare reform bill made him the candidate of choice for Labour’s left.

Khan, who will face the Conservatives’ Zac Goldsmith in May, is now the favourite to become the first Labour London mayor since 2008. There are few more energetic campaigners in British politics and Tories privately concede that Goldsmith cannot match Boris Johnson’s appeal. The most recent YouGov poll showed him trailing his rival by six points.

But Khan, who immediately distanced himself from Corbyn following the latter’s victory, will be endlessly reminded by the Conservatives of his nomination of the Labour leader. His challenge will be to maintain his independent image while also harnessing the support of the thousands of Corbynite activists. If he succeeds, he will immediately become the most powerful Labour politician to hold executive office.

Losers

Ed Miliband

Until the moment the exit poll was released, Ed Miliband believed he would become prime minister. Fourteen hours later, he had resigned, condemned to join the long list of failed Labour leaders. In common with many others, no one in Miliband’s circle had prepared for the possibility of a Conservative majority.

So baleful was the result that many in Labour immediately concluded that the 2020 election was lost too. The party retained just one of its 40 Scottish seats, fell further behind the Conservatives in English marginals and made a net loss of 26.

Most painfully for Miliband, the defeat came in part because of him, rather than in spite of him. His personal ratings long trailed those of Labour and David Cameron and he was never regarded as a prime minister-in-waiting by the electorate.

When Jeremy Corbyn was elected leader Miliband was blamed by some for introducing the one-member-one-vote electoral system, repudiating New Labour and allowing the selection of left-wing candidates. Miliband, who privately favoured Andy Burnham, resisted calls to intervene during the contest.

Unlike former colleagues such as Ed Balls, Douglas Alexander and Jim Murphy, all of whom lost their seats, Miliband exists in a state of limbo. Having chose not to stand down or to serve in Corbyn’s shadow cabinet, he is seeking to re-establish himself by campaigning on inequality and climate change. Allies speak of how he could follow the path of former Tory leaders William Hague and Iain Duncan Smith and one day return to the frontline.

George Osborne’s post-election Budget paid homage to Miliband with its introduction of a National Living Wage and an apprenticeship levy on business. Many in both main parties speak of how the Labour leader asked the right questions even if the answers fell short. But none of this is adequate consolation for losing the prize he always believed was within his grasp.

Nick Clegg

There were two beliefs that consoled Nick Clegg through the long years of subterranean poll ratings. The first was that the Liberal Democrats would retain at least half of their existing seats, the second was that they would return to government in another hung parliament.

On 7 May, both of these beliefs were destroyed. One of Clegg’s predecessors, Paddy Ashdown, declared that he would “eat his hat” if the exit poll forecasting 10 Lib Dem seats was right. The poll was indeed wrong - but in the opposite direction. The Lib Dems held just eight and lost senior figures such as Vince Cable, Danny Alexander, David Laws and Ed Davey. Even in a hung parliament, the Conservatives would almost certainly have taken office as a minority government.

Against some predictions, Clegg retained his Sheffield Hallam seat but the result made his resignation as leader inevitable. His assertion that electorate would eventually give the Lib Dems credit for their role in the coalition proved fundamentally mistaken.

Clegg’s hope was that British politics had entered a new era of hung politics that would break the red-blue duopoly. The coalition may now prove a mere footnote to a long period of Conservative rule. There is no defining achievement, such as electoral reform, for which the Lib Dems will be remembered.

Few, including new leader Tim Farron (elected as a left-leaning alternative), believe that the party will recover in the near future. Should its humbling prove permanent, it is Clegg’s fateful decision to enter government with the Lib Dems’ sworn opponents that will be blamed.

Nigel Farage

2015 was supposed to be Ukip’s breakthrough year. After winning the European elections and capturing Tory defectors Douglas Carswell and Mark Reckless, Nigel Farage boasted of targeting 30 seats and predicted that he would hold the balance of power in a hung parliament.

Ukip more than quadrupled its vote share, finishing ahead of the Lib Dems in third place. But its evenly-distributed support, a curse under first past the post, meant it was left with just a solitary seat.

To intensify Farage’s woes, he again failed to enter parliament at the seventh time of trying.

The Ukip leader immediately fulfilled his pre-election pledge to resign if defeated, only to reverse his decision three days later. His obstinacy brought the party’s underlying tensions to the surface as economic spokesman and MEP Patrick O’Flynn denounced him as a “snarling, thin-skinned, aggressive” man who was turning Ukip into a personality cult.

The party’s divisions have endured since, with Carswell, its sole MP, publicly calling for Farage to resign. Ukip is torn between libertarians such as Carswell, who urge a more socially liberal line, and anti-immigration conservatives.

In 2016, these divisions threaten to distract from the cause for which the party was founded: British withdrawal from the European Union. EU opponents speak of their fear that Farage will contaminate the anti-Brussels case and deny them a majority in the referendum. But if the public vote to leave it is the Ukip leader, who helped force David Cameron’s concession, who will deserve much of the credit.

Andy Burnham

When Labour was defeated and Ed Miliband resigned it appeared that Andy Burnham’s moment had arrived. Over the preceding year, the former health secretary had established himself as the darling of activists and the trade unions. As the contest began, he was swiftly installed as the favourite.

It was the right that Burnham’s team regarded as a threat. He began his campaign with a paean to business at EY, criticised Miliband’s “mansion tax” and warned of potential further welfare cuts. “The left have nowhere else to go,” one of his senior allies said. But Jeremy Corbyn’s unexpected arrival on the ballot destroyed this calculation. The left had somewhere else to go - and went there in epic numbers.

Burnham’s refusal to vote against the welfare bill, having initially led the revolt against Harriet Harman’s stance, only enhanced the appeal of Corbyn’s unambiguous socialism. The shadow health secretary found himself denounced by the left and the right as a “flip-flopper”.

While Yvette Cooper was praised for her early intervention on refugees, and Liz Kendall was admired for her tenacity in the face of certain defeat, Burnham’s campaign attracted increasing derision. Against some predictions, he finished second but trailed far behind Corbyn.

Burnham, who was the only candidate to join the new leader’s shadow cabinet, ruled out a third bid during the contest. But allies suggest he could yet offer himself as a “unifying” figure if Corbyn is removed. For now, though, Burnham can only reflect on how far he fell short.