The UK prime minister, Rishi Sunak, has called a general election for 4 July, kicking off a six-week campaign that could see his Conservative party ejected from power after 14 years. Why has Sunak called the general election now? The UK has begun to emerge from a “cost of living crisis” that had seen the prices of essential goods rocket since Russia invaded Ukraine two years ago. Sunak’s message to the country is that the economy is on the right track, and only his party can deliver stability. Many observers had expected the poll to be held in the autumn – perhaps in October or November – but Sunak appears to believe the prospects for his party are unlikely to improve between now and then, and he perhaps hoped an element of surprise would allow him to steal a march on the opposition Labour party, led by Keir Starmer. What happens next? Sunak has been granted permission from the king to “dissolve parliament” – a power formally held by the British monarch, though it is effectively the prime minister’s decision. After 30 May, the current parliament formally ceases to exist, and its MPs become candidates – who will have to make the case to voters that they should be re-elected. Government ministers continue in their posts carrying out their duties until a new administration has been formed. Is Sunak likely to lose? Certainly if opinion polls are correct: Keir Starmer’s Labour party has held a significant lead over the Conservatives for months now, and most experts expect a relatively comfortable victory for Labour. However, election campaigns can sometimes alter the result – as in 2017, when the Conservative prime minister Theresa May called an election while leading in the polls, but went on to lose her majority after a disastrous campaign. She then had to govern in partnership with Northern Ireland’s Democratic Unionist party (DUP). What are the key issues at stake? Both parties claim to be able to offer economic stability – though Labour can point to the chaotic period under Sunak’s predecessor, Liz Truss, during which mortgage rates rocketed, and will ask voters whether they feel better off after 14 years of Conservative rule. Labour, whose key slogan is “Change”, will also focus on the state of public services, in particular the National Health Service, where waiting lists have grown significantly. Both parties will claim to be tough on migration: Sunak has repeatedly promised to “stop the boats”, but Labour argues his plan to send people who come to the UK by illegal routes to be resettled in Rwanda is costly and impractical. How are other political parties likely to fare? The Liberal Democrats, led by Ed Davey, who was a minister in the 2010-15 government in power alongside the Conservatives, hope to challenge Sunak’s party in a string of seats across the south of the UK. Many of these are held by senior ministers, including the chancellor, Jeremy Hunt, whom the Lib Dems hope to unseat. The Green party, which only has one MP at Westminster, hopes to win another seat, in the city of Bristol, in addition to its one in Brighton after performing strongly in recent local elections. The Scottish National party, which campaigns for Scottish independence, is now the third largest, with 43 MPs. But after a tumultuous period which recently saw its leader Humza Yusuf resign as Scotland’s first minister, Labour has high hopes of winning seats from the SNP in Scotland – helping it to a majority across the UK as a whole. How will the campaign be conducted? Through a furious “air war”, in which the party leaders pitch to be the UK’s prime minister through manifestos, glitzy launches and head-to-head debates; and, at the same time, through 650 individual races to become local MPs. The grassroots battles involve a less glamorous “ground war”, with thousands of activists knocking on doors, delivering leaflets and having conversations with individual voters. What happens on polling day? The polls open at 7am and close at 10pm on polling day, with most voters attending in person to mark their preference in pencil and post the paper into a plastic ballot box. At the close of the polls, an exit poll is published, which tends to correctly predict the result. The results from each constituency start to emerge throughout the night as local officials count the piles of paper ballots. By the morning, it tends to be clear who the winner is. What happens next? If Labour wins the election with an outright majority, Starmer would move quickly to announce a new ministerial team, with a series of significant challenges to face almost immediately – including hosting a major European summit at the English country estate of Blenheim Palace on 18 July. Will Sunak remain as an MP? He says yes: asked on the TV chatshow Loose Women last week, the prime minister said he loved his home in the Yorkshire constituency of Richmond – where he has been building an indoor swimming pool – and would stay on to represent his constituents. But many at Westminster expect that, like David Cameron, who promised to stay on after the Brexit referendum and swiftly resigned when he lost, Sunak would leave parliament if he lost on 4 July. Sunak and his wife, Akshata Murty, have a property in California, where they met, and he has previously spoken warmly about the entrepreneurial culture of the US.