All the key dates you need to know about - from the turn of the year to day we vote.
January 4th: Parliament returns with a bang as Labour and Tories go head to head in a day that gave voters a taste of the general election campaign. The government made announcements on education and the economy while David Cameron concentrated on the NHS. A day earlier, Gordon Brown's confirmation of a March Budget reinforced assumptions that the election would take place on May 6th.
January 5th: The judgement comes in on the start of the election campaign with most commentators giving Labour first blood. Cameron's dither over married couples' recognition in the tax system saw him go from doubt to certainty and analysts sensed an uncertainty in the Tory election machine.
January 6th: http://www.politics.co.uk/news/legal-and-constitutional/westminster-in-chaos-as-new-brown-plot-emerges-$1351590.htm. Just as Brown enjoys the good press of Tory mistakes and a particularly confident PMQs performance, a letter goes out to all Labour MPs from Geoff Hoon and Patricia Hewitt calling for a secret leadership ballot. They receive no support and soon enough both announced they were stepping down at the next election. But ministers took hours to express support for Brown and their lukewarm tones prompted fierce doubts about his Cabinet's loyalty.
January 13th: Cameron's airbrushed poster backfires when Brown takes him apart for it at PMQs. "He looks very different from the poster," Brown joked. "If you can't get your photograph right it's very difficult to get your policies right." On the internet, various spoofed versions of the poster crop up, a trend that would be followed whenever new posters were unveiled. Most contributions were very funny, but they revealed a vulnerability in the Tories' PR operation.
January 22nd: Brown's appearance before the Iraq inquiry is set for before the election. Sir John Chilcot had originally set the date for after the election, in a bid to stop it turning into a party political bonanza, but a campaign by opposition parties eventually saw Brown offer himself up for an earlier date.
January 26th: The UK emerges from recession - barely. At 0.1% growth in the last quarter of 2009, the figures weren't exactly the glorious evidence of successful economic policy Labour wanted. But from that point onwards the party's poll ratings start to improve. Analysts point to Tory uncertainty on key policies and increased public concern at proposed Tory cuts, but few doubt the tentative economic recovery helps Labour's chances.
January 29th: Blair appears before the Iraq inquiry. His appearance, which sees him refuse to apologise and repeatedly call for an attack on Iran, does not damage Labour's prospects as much as some analysts had predicted.
February 2nd: A ComRes poll for the Independent shows the Tory lead slipping to seven points, within the margin for a hung parliament. The Tory poll lead stubbornly refuses to improve throughout the month. Speculation about the weakness of the Tory campaign gathers becomes increasingly shrill.
February 4th: Sir Thomas Legg's report into how many MPs will have to pay back their expenses is finally released, bringing the scandal back onto the front pages. A total of 390 MPs - around half the House of Commons - are ordered to pay back £1.3 million. As before, all parties are damaged equally.
February 6th: The Crown Prosecution Service (CPS) announces three Labour MPs and one Tory peer will face charges of false accounting for their expenses. Suggestions that the group might cite parliamentary privilege prompt anger in the Commons and Labour quickly removes the whip from the MPs in question.
February 9th: A row breaks out over elderly care, with the Conservatives branding government policy 'Brown's death tax'. As the row goes on, it emerges that health spokesmen from all three main parties had met to discuss proposals, but the meeting ended in bitter acrimony. Polling later shows most voters like Labour's policies and the Tory 'death tax' poster goes down as badly as the earlier 'airbrushed' one. That evening, MPs agree to hold a referendum on electoral reform if Labour win power, after an epic late-evening debate. The Tories brand it a desperate attempt to change the rules of the game from a dying government.
February 14th: Brown's emotional interview with Piers Morgan on ITV nets 4.2 million viewers. It reveals the prime minister's human side, with a section showing him crying over the death of his daughter enjoying substantial pre-broadcast publicity. Later polling shows it neither damages nor particularly improves his standing.
February 19th: Sixty economists write a letter to the Financial Times backing the government's decision not to threaten the economic recovery by cutting spending this financial year. The letter follows a similar intervention by economists in a letter to the Sunday Times days earlier backing the Tory position of quicker cuts. With economists at war, the public struggles to make up its mind.
February 19th: James Purnell announces he will step down at the general election. The departure of the former work and pensions secretary, who tried unsuccessfully to trigger a leadership contest against Brown with his resignation in 2009, leaves few Blairites with Cabinet experience in the party. It is also taken as a sign that young, bright, ambitious Labour MPs are leaving a sinking ship.
February 20th: Brown unveils the new Labour campaign slogan, 'a future fair for all', at Warwick University. The launch is accompanied by several Cabinet members and is well-received. The Tories continue to struggle in the polls.
February 21st: Just a day after his launch won decent reviews, Brown is once again mired in scandal. Andrew Rawnsley's book, serialised in the Observer, alleges the head of the civil service had to speak to the prime minister personally about the way he treats junior staff. The bullying row rages throughout the week, although polling does not show any substantial damage to Labour's support.
February 23rd: The bullying row takes a major new turn with a flabbergasting interview on Sky News in which chancellor Alistair Darling admits Downing Street unleashed the "forces of hell" against him when he predicted the worst recession for 60 years back in 2008. The remarks remind everyone of the fragile unity of the Labour campaign, and the strained relations between Brown and his chancellor. The next day, Cameron uses the interview to score a convincing win over Brown at PMQs.
March 1st: Michael Ashcroft admits he's a non-dom. The revelation throws the Tory party into crisis, after concerns are raised about why it has evaded answers about their deputy chairman's tax status for a decade. The Tory leader when Lord Ashcroft was granted his peerage, William Hague, admits that he only learnt of the news months ago. This complicates matters further when David Cameron says he learnt one month ago.
March 2nd: After weeks of speculation The leaders' live TV debates get the go-ahead . ITV, Sky and BBC are granted one each, on the subjects of domestic affairs, foreign affairs and the economy.
March 4th: Ashcroft's donations to the Tory party are judged to be legal by the Electoral Commission, although the controversy continues to plague the party.
March 5th: Brown appears in front of the Chilcot inquiry into the Iraq war. His performance is assured, but he is later forced to admit he inadvertently misled the inquiry over defence spending.
March 13th: Brown finally condemns the British Airways strike, calling it "deplorable". The Labour party's donations from strike organisers Unite cause the prime minister to suffer considerable political damage in the build up to industrial action.
March 17th: Good news for Labour as unemployment levels fall again. The improved economic forecast substantiates the party's claims that it took the right action during the financial crisis.
March 22nd: Three former Labour ministers are suspended after a joint investigation by the Sunday Times and Channel 4's Dispatches programme reveals them to have accepted offers from a fake lobbying firm in exchange for exerting their influence on policy. Stephen Byers, Patricia Hewitt and Geoff Hoon's political careers are effectively ended. The row puts pressure on Labour but opinion polls show the party did not suffer significantly.
March 24th: Labour aims for its core vote with a redistributive Budget. Darling is condemned in some quarters for not tackling the deficit, but most commentators are unsurprised by a Budget which offers neither sweeteners nor painful cuts.">
March 29th: The three would-be chancellors debate live on Channel 4. Vince Cable is branded the winner by most observers, including those contributing to an online poll. Earlier in the day, shadow chancellor George Osborne announces the Tories will scrap Labour's national insurance tax rise, leading to an embattled performance in front of the cameras.
April 6th: Brown announces the election, flanked by his Cabinet outside Downing Street. Cameron hits the ground running, launching his campaign before Brown has even made the announcement. Clegg rouses party workers with a speech preparing them for the month ahead.
April 7th http://www.politics.co.uk/news/legal-and-constitutional/tories-jubilant-in-final-pmqs-$1369409.htm sees Cameron attack Brown for a variety of offences. "As this is the last PMQs this parliament it is the last chance for this prime minister to show he is accountable for the decisions he has made," Cameron said. Brown retorted by using one of Cameron's old lines: "To think he was the future once."
April 12th: Labour unveils its manifesto in the Midlands. Brown's accompanying speech sees him promise to reform both the state and the market.
April 13th: The Conservatives unveil their manifesto at Battersea Powerstation. Activists wearing blue 'we're all in this together' T-shirts mingled with the shadow cabinet as Cameron promised a revolution in 'people power'.
April 14th: Nick Clegg launches the Liberal Democrat manifesto in London, to little fanfare. His pledge to 'hardwire' fairness into British society is adopted as the headline, but his opening comment that everyone is extraordinary is mocked by sketch writers for its contradictory nature.
April 15th: The leaders' TV debate on ITV pulls nine million viewers and sees Clegg emerge the easy winner. Many analysts are struck by the weakness of Cameron's performance while Brown does better than expected. Within moments of the debate starting, most political pundits conclude the event will become an electoral tradition.
April 18th - A unprecedented surge in Liberal Democrat support sees it climb to first place in some polls, a situation which would have been unthinkable just days ago. A separate poll put the Lib Dems in second place, while another sees them taking votes off the Tories and coming up strongly behind Labour.
April 21st - Clegg lashes out at Gordon Brown in a newspaper article which sees him brand the prime minister "desperate". With a hung parliament distinctly possible, the article is interpreted as proof that the Lib Dems would insist on a change of PM if they entered into a coalition with Labour.
April 28th - Brown commits the most serious gaffe of the campaign when he brands a Labour voter a bigot. He later apologises in person after a four hour media frenzy, but the damage is already done.
April 29th: The final leaders' TV debate, on the economy, is shown on the BBC. There are few surprises, but many polls give a slim lead to David Cameron, with the Tory leader vastly improving on his nervous early performance. Labour support continues to decline, and the Lib Dems are widely considered the main challengers to the Conservatives.
May 6th: Britain goes to the polls. Results will start coming in in the early morning.