The Liberal Democrats achieved a breakthrough in opinion polls following the first debate, in which their leader Nick Clegg was widely seen as the strongest performer.

A hung parliament had been largely anticipated by the opinion polls in the run-up to the election, so politicians and voters were better prepared for the constitutional process that would follow such a result than they had been in 1974.

Realising that a deal between the Conservatives and the Liberal Democrats was imminent, Brown resigned the next day, on Tuesday 11 May, as prime minister, marking the end of 13 years of Labour government.

[24] Nick Clegg[25] and Menzies Campbell[26] had continued the position of Charles Kennedy of not being prepared to form a coalition with either main party and of voting against any Queen's Speech unless there was an unambiguous commitment in it to introduce proportional representation.

[29] However, this caused the sole UUP MP Lady Sylvia Hermon to resign from the party on 25 March 2010, leaving them with no representation at Westminster for the first time in their history.

Farage was replaced in an election by party members by Lord Pearson of Rannoch, whose stated intention was for the electoral support of UKIP to force a hung parliament.

The Green Party of England and Wales voted to have a position of leader for the first time; the first leadership election was won by Caroline Lucas, who successfully contested the constituency of Brighton Pavilion.

[36][37][38][39] Philip Lardner, the Conservative candidate for North Ayrshire and Arran, was suspended from the party for comments he made about homosexuality on his website, describing it as not "normal behaviour".

[43] The Labour candidate for Bristol East and former MP Kerry McCarthy revealed information about postal votes cast in the constituency on Twitter.

"[50][51] In a private conversation with his communications director Justin Forsyth following the meeting, Brown described Duffy as "just a sort of bigoted woman that said she used be Labour.

The Labour candidate for North West Norfolk, Manish Sood, described Gordon Brown as Britain's worst ever prime minister.

[62] The comments, which he repeated to a variety of news outlets, took attention away from the previous day's speech by Brown to Citizens UK, widely described as his best in the campaign.

[66] On the morning of polling day, 6 May, the former and later leader of UKIP, Nigel Farage, standing in Buckingham against the Speaker, was injured when a light banner-towing aircraft in which he was a passenger crashed near Brackley, Northamptonshire.

By the end of February 2010, Ipsos MORI, ICM, YouGov and ComRes polls had all found a sufficient narrowing of the Conservative lead for media speculation about a hung parliament to return.

The Independent and The Guardian advocated tactical voting to maximise the chance of a Liberal Democrat/Labour coalition to make electoral reform including of the House of Lords and introduction of domestic proportional representation more likely.

[107] On 28 May 2010, the defeated Liberal Democrat candidate Elwyn Watkins lodged a petition against the election of Phil Woolas (Labour) in Oldham East and Saddleworth constituency.

[108] The petition challenged leaflets issued by Woolas's campaign as having contained false statements of fact concerning Watkins' personal character, which is an illegal practice under section 106 of the Representation of the People Act 1983.

The statements attempted to link Watkins with Muslim extremists and death threats to Woolas, accused him of reneging on a promise to live in the constituency, and implied that his campaign was funded by illegal foreign political donations.

[113] On that day Woolas was found to have breached section 106 of the Representation of the People Act 1983 in relation to three of the four statements complained about, and the judges ruled that his election was void.

[114] Phil Woolas applied for a judicial review into the ruling,[115] stating that "this election petition raised fundamental issues about the freedom to question and criticise politicians" and that it "will inevitably chill political speech".

Sir Reg Empey, leader of the UUP/Conservative alliance (UCUNF), standing for the first time in South Antrim, lost to the DUP incumbent William McCrea.

New SDLP leader Margaret Ritchie, succeeding Eddie McGrady MP, won against Sinn Féin's Caitriona Ruane in South Down.

Among them were Margaret Moran,[136] Elliot Morley,[137] David Chaytor,[138] Nicholas and Ann Winterton,[139] Derek Conway,[140] John Gummer,[141] Douglas Hogg,[142] Anthony Steen,[143] Peter Viggers,[144] Julie Kirkbride and her husband Andrew MacKay.

Hazel Blears, who had paid more than £13,000 to cover capital gains tax which she had avoided by "flipping" the designation of her main residence,[153] suffered a large drop in her vote in Salford and Eccles, but was still comfortably re-elected; a 'Hazel must go' candidate won only 1.8%.

[154] Conversely, Brian Jenkins lost his Tamworth seat on a large 9.5% swing despite being described as a "saint" by The Daily Telegraph on account of his low expenses.

[155] Ironically, his successor in the seat was Conservative Chris Pincher, whose future sexual assault scandal would bring down the premiership of Prime Minister Boris Johnson twelve years later.

An imperfectly observed convention states that the major parties do not oppose the Speaker seeking re-election; Bercow faced two main opponents in Buckingham.

[162] In Liverpool, higher-than-expected turnout meant several polling stations ran out of ballot papers, with defeated council leader Warren Bradley stating that some residents were unable to cast their votes.

On 11 May 2010, as coalition talks between the Conservatives and the Liberal Democrats seemed to be drawing to a successful conclusion,[4] Gordon Brown announced that he was resigning as prime minister and also as Labour leader.

He then left Downing Street, accompanied by his wife and children, driving to Buckingham Palace where he tendered his resignation to the Queen and advised her to call for David Cameron.