Boris Johnson and Jeremy Corbyn will face each other later in the first TV debate of the election campaign.
The head-to-head between the Conservative and Labour leaders, hosted by news presenter Julie Etchingham, will be shown on ITV at 20:00 GMT.
It comes after the Lib Dems and SNP lost their legal challenge to be included in the live programme.
Labour leader Mr Corbyn was the first to arrive at Media City in Salford, where the debate is being held.
He was greeted by cheering supporters telling them: “I am loving every minute of it and I am utterly, utterly determined that we are going to win this election to make life better for those that have suffered so much under austerity.”
He told reporters he hoped it would be “a respectful and informative debate”.
Asked if he was nervous, he said: “Not in the slightest. Why would I be?
“I am very confident in our policies and our ability to try and transform this country.”
Asked how he had prepared for the debate, he said he had “eaten a Caesar salad, had a couple of cups of tea, read a bit and talked a bit to my team”.
Labour grassroots campaign Momentum said supporters of Mr Corbyn were organising “watch parties” around the UK and in France, Israel, Germany and Spain.
The head-to-head debate is scheduled to be followed at 22:00 by interviews with party leaders, including Liberal Democrat leader Jo Swinson, reacting to the debate.
News presenter Julie Etchingham told BBC Radio 4’s Today programme that chairing the debate was a “hard thing to navigate if they won’t engage and debate with each other”.
Her role would then be to put specific points to each of them, she said, adding: “The best debates are when they debate and engage properly with one another.”
She said ITV had received hundreds of questions “across a whole range of subjects” from their viewers, so the broadcaster knows what questions the public wants answered.
This is the first time we will have just two prime ministerial candidates head-to-head.
Last time we had anything like this was in 2010 when three people were in the ring – not just Gordon Brown and David Cameron, there was Nick Clegg too and that did provide a change in the dynamic because of that brief upsurge in “Clegg-mania”.
So these debates have the potential to change the dynamic, but very often they do not.
In part, I think because both sides tend to be so well prepared, so well drilled, they are so familiar with each other’s arguments.
And we see so much of our political leaders now our views of them are pretty well grounded. It will have to be an almighty zinger or an extraordinary clanger for it to be a really game-changing moment.
In terms of choreography for tonight, half of it will be devoted to Brexit so actually that plays to Boris Johnson.
He wants it to be about Brexit, he wants the election to be about Brexit, and he’s going to get half of tonight’s one-hour programme on his core subject.
The second half will be covering absolutely everything else, from foreign affairs to the economy to education to home affairs.
On Monday, in London’s High Court, the Lib Dems said they wanted their pro-Remain stance to be represented, while the SNP also wanted the issue of Scottish independence to be raised.
But Lord Justice Davis and Mr Justice Warby said the case was not suitable for judicial review as ITV was not carrying out a “public function” in law by holding the debate.
However, the parties had the right to complain to Ofcom about the programme after it had been broadcast, they said.
The BBC will also host a live head-to-head debate between the Conservative and Labour leaders in Southampton on 6 December, plus a seven-way podium debate between senior figures from the UK’s major political parties on 29 November, live from Cardiff.
The Lib Dems have sent a legal letter to the BBC over its decision not to include Ms Swinson in the head-to-head.
BBC Scotland will stage a televised debate between the SNP, Conservatives, Labour and Liberal Democrats on 10 December, although the Scottish Greens have criticised the decision not to include them.
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here for a list of election terms and what they mean.
Term for an MP who is not a minister. They sit behind the front benches in the House of commons.
Ballot
Another term for vote.
Ballot box
A sealed box with a slit in the lid. Voters place their ballot papers through the slit into the box. When polls close the boxes are opened and counting begins.
Ballot paper
Paper containing a list of all candidates standing in a constituency. Voters mark their choice with a cross.
By-election
An election held between general elections, usually because the sitting MP has died or resigned.
Candidate
Someone putting themselves up for election. Once Parliament has been dissolved, there are no MPs, only candidates.
Canvassing
During a campaign, active supporters of a party ask voters who they will vote for and try to drum up support for their own candidates.
Close of nominations
The deadline for candidates standing to send in the officials forms confirming their place in the election. This is usually __ days before polling day.
Coalition
When two or more parties govern together, when neither has an overall majority. After the 2010 election, the Conservatives and Lib Dems formed a coalition, which lasted for five years.
Confidence and supply
A agreement between two political parties where the smaller party agrees to support a larger one without enough MPs to have a majority in parliament.
Conservative
The Conservative party is
Constituency
The geographical unit which elects a single MP. There are 650 in the UK.
Dead cat
In politics, a ‘dead cat’ strategy is when a dramatic or sensational story is disclosed to divert attention away from something more damaging. The term comes from the concept of an imaginary dead cat being flung onto a dining table, causing the diners to become distracted by it.
Declaration
The announcement of the election result in each constituency.
Deposit
A sum of £500 paid by candidates or their parties to be allowed to stand. It is returned if the candidate wins 5% or more of the votes cast.
Devolution
The delegation of powers to other parliaments within the UK, specifically the Scottish Parliament and Welsh and Northern Ireland Assemblies.
Devolved parliament
The Scottish Parliament and Welsh and Northern Ireland assemblies are elected by voters in those nations of the UK. They make laws on policy areas controlled by those nations such as health, environment and education.
Dissolution of Parliament
The act of ending a Parliament before an election. When parliament is dissolved there are no MPs, but the prime minister and other senior ministers remain in their roles.
Electoral register / roll
A list of everyone in a constituency entitled to vote. Also known as electoral roll.
Exit poll
An exit poll is a poll of voters leaving a voting station. They are asked how they have voted, and the results are used to forecast what the overall result of the election may be.
First past the post
Term used to describe the UK’s parliamentary election system. It means a candidate only needs to win the most votes in their constituency to win the seat.
Gain
When a party wins a constituency from another party, it is said to have “gained” it from the other.
General election
Election at which all seats in the House of Commons are contested.
Hung parliament
If after an election no party has an overall majority, then parliament is said to be “hung”. The main parties will then try to form a coalition with one or more of the minor parties. Opinion polls have suggested that a hung parliament is a strong possibility after the 2015 general election.
Hustings
A meeting a which candidates address potential voters. The word comes from an old Norse word meaning “house of assembly”.
Independent
A candidate who is not a member of any political party and is standing on their own personal platform. To qualify as an official political party, a party must be registered with the Electoral Commission, the organisation which administers elections in the UK.
Landslide
The name given to an election which one party wins by a very large margin. Famous landslides in UK elections include Labour’s victory in 1945, the Conservative win in 1983 and the election which brought Tony Blair to power in 1997.
Left wing
A person or party with strong socialist policies or beliefs.
Liberal Democrat
The name of the party occupying the centre ground of British politics. They were formed from the former Liberal party and Social Democrats, a Labour splinter group, and combine support for traditional liberalism such as religious tolerance and individual freedom, with support for social justice.
Majority
A majority in Parliament means one side has at least one more vote than all the other parties combined and is therefore more likely to be able to push through any legislative plans.
Majority government
When one party wins more than half of the seats in the Commons, they can rule alone in a majority government
Mandate
Politicians say they have a mandate, or authority, to carry out a policy when they have the backing of the electorate.
Manifesto
A public declaration of a party’s ideas and policies, usually printed during the campaign. Once in power, a government is often judged by how many of its manifesto promises it manages to deliver.
Marginal
Seats where the gap between the two or more leading parties is relatively small. Often regarded as less than a 10% margin or requiring a swing (see below) of 5% or less, though very dependent on prevailing political conditions.
Minority government
A minority government is one that does not have a majority of the seats in Parliament. It means the government is less likely to be able to push through any legislative programme. Boris Johnson has suffered a number of defeats in Parliament over a no-deal Brexit because he does not have a majority.
MP
Strictly this includes members of the House of Lords, but in practice means only members of the House of Commons. When an election is called Parliament is dissolved and there are no more MPs until it assembles again.
Nomination papers
A candidate must be nominated on these documents by 10 voters living in the constituency.
Opinion poll
A survey asking people’s opinion on one or more issues. In an election campaign, the key question is usually about which party people will vote for.
Opposition
The largest party not in government is known as the official opposition. It receives extra parliamentary funding in recognition of its status.
Party Election Broadcast
Broadcasts made by the parties and transmitted on TV or radio. By agreement with the broadcasters, each party is allowed a certain number according to its election strength and number of candidates fielded.
Percentage swing
The swing shows how far voter support for a party has changed between elections. It is calculated by comparing the percentage of the vote won in a particular election to the figure obtained in the previous election.
Polling day
Election day
Polling station
Place where people go to cast their votes
Postal vote
People unable to get to a polling station are allowed to vote by post if they apply in advance.
Proportional representation (PR)
Any voting system where the share of seats represents the share of votes is described as proportional representation. The UK currently has a first past the post system.
Prorogation
Parliament is usually prorogued, or suspended, ahead of an election or Queen’s Speech to allow for preparations. In September 2019 Boris Johnson attempted to prorogue Parliament for five weeks, but the Supreme Court later ruled the prorogation unlawful and MPs returned to Parliament.
Psephologist
A person who studies voting and voting patterns.
Purdah
This is the time between the announcement of an election and the final election results. During this period media organisations have to ensure any political reporting is balanced and is not likely to influence the outcome of the election.
Recount
If a result is close, any candidate may ask for a recount. The process can be repeated several times if necessary until the candidates are satisfied. The returning officer has the final say on whether a recount takes place.
Returning officer
The official in charge of elections in each of the constituencies. On election night they read out the results for each candidate in alphabetical order by surname.
Right wing
Someone who is right wing in politics usually supports tradition and authority, as well as capitalism. The Conservative party is regarded as the main centre-right party in the UK.
Safe seat
A safe seat is a constituency where an MP has a sufficiently large majority to be considered unwinnable by the opposition.
Spin room
The attempt to place a favourable interpretation on an event so that people or the media will interpret it in that way. Those performing this act are known as spin doctors.
Spoiled ballot
Any ballot paper that is not marked clearly, eg with more than one box ticked or with writing scrawled across it, is described as a spoiled ballot and does not count towards the result.
Tactical voting
This is when people vote not for the party they really support, but for another party in order to keep out a more disliked rival.
Target seat
In theory, any seat that a party contests and held by a rival is one of its targets. In practice, a target seat is one that a party believes it can win and puts a lot of effort into doing so.
Turnout
Turnout is the percentage of eligible voters who cast a ballot on polling day.
Vote of no confidence
It is usually the leader of the opposition, currently Jeremy Corby, who calls for a vote of no confidence, in an attempt to topple the government. If more MPs vote for the motion than against it, then the government has 14 days to try to win back the confidence of MPs through another vote – while the opposition parties try to form an alternative government. If nothing is resolved, then a general election is triggered.
Westminster
The UK Parliament is located in the Palace of Westminster in the centre of London and the term is often used as an alternative to Parliament.
Working majority
A working majority in Parliament is what a government needs to carry out its legislative programme without risk of defeat. It means the government can rely on at least one more vote than the opposition parties. However, in the current Parliament, the government no longer has a majority and MPs from a range of opposition parties have joined forces to form a parliamentary majority big enough to defeat the government over plans for a no-deal Brexit.