David Cameron and Nick Clegg will today go head to head on plans to reform Britain's voting system – but with speeches that have been seen by each other's teams in advance.
In a sign of the strange way that the Coalition partners intend to conduct the campaign, both leaders agreed to give speeches within hours of one another. They will put forward their side of the argument, but they will avoid attacking each other directly.
Tory and Liberal Democrat aides have also consulted each other on the key themes each man will present.
A referendum on changing the voting system for general elections will take place on 5 May; the Government has finally overcome resistance from the House of Lords to get the legislation through Parliament. The Parliamentary Voting System and Constituencies Bill received royal assent late on Wednesday after a lengthy passage through the Commons and Lords.
First up today will be Mr Clegg, who will travel to Leeds to speak to Liberal Democrat party members. He is expected to argue that under the alternative vote (AV) system, fewer MPs will have a "job for life".
"First past the post makes it easy for MPs to get complacent and lazy," he will say. "Under the alternative vote, politicians will need to aim to get half of their constituents to choose them. That means they will have to work harder to appeal to more people than before.
"It means they will have to reach out to people who were ignored under first past the post. It means they will no longer be able to rely on just their core supporters and ignore everyone else."
In contrast, Mr Cameron will argue that AV would make politics less accountable: "First past the post is often decisive – and sometimes ruthlessly so. It has the habit of rising to the occasion. Be it in 1979 and yes, 1997. It recognised that the Government of the day had had its day.
"There's nothing more powerful than that – when people see their vote has led to the removal vans driving down Downing Street."
Mr Cameron is expected to argue that Gordon Brown would very likely still be prime minister under AV – a slightly strange claim, given it was a hung Parliament that led to the Tory-Liberal Democrat Coalition. "Any system that keeps dead governments living on life support is a massive step backward for accountability and trust in our politics," he will say.
Mr Cameron is keen to stress that he will be making his case "loud and clearly" in the run up to 5 May. But there is an expectation that both leaders will take a backseat to the official campaigns – in part because they fear their presence may put off prospective voters.
Liberal Democrat aides said Mr Clegg would be making at least one more speech on AV but stressed he would be concentrating on the local elections which are being held on the same day. Mr Cameron will be under more pressure from his backbenchers to take on a higher-profile role. But both men have agreed that the referendum – whichever way the vote goes – is less important than the stability of the Coalition and the necessity of seeing the Government complete a full term.
The No2Av campaign plans to focus its efforts on framing the referendum as a vote on the popularity of Mr Clegg, highlighting the cost of the reform. In contrast, the Yes campaign hopes to portray itself as a grassroots movement – which is opposed to any one faction in Westminster.
Jenny Watson, chairman of the Electoral Commission and chief counting officer for the referendum, said they were on-track with the referendum plans. "Now the Bill has passed into law, we have the certainty we need to deliver on our plans for successful polls on 5 May," she said.
"We'll continue to work with the hundreds of local counting officers across the UK, making sure that they have the plans in place to ensure voters have the best possible experience at the elections and referendum."
The commission will now press ahead with plans to send an information booklet to all 27.8 million UK households. It will also start to register campaigners for the referendum and to receive applications to become the official lead campaigners for a Yes and No vote.
The full text of the question voters will be asked on 5 May is:
"Do you want the United Kingdom to adopt the 'alternative vote' system instead of the current 'first past the post' system for electing Members of Parliament to the House of Commons?"
How does the Alternative Vote work?
Instead of marking the ballot paper with an "X" for one candidate, the voter can rank all the candidates in order of preference.
If one candidate receives a majority of first-preference votes, then that person is elected. If no candidate gains a majority of first-preference votes, then the second-preference votes of the candidate who finishes last on the first count are redistributed. This process is repeated until someone gets over 50 per cent.
So,which side of the argument are you on?
Cameron's No camp
John Prescott Yes campaigners will try to target him as the weakest link in the No camp.
Margaret Beckett Former deputy Labour leader, now President of the No campaign.
John Reid Expect to see him putting the No case on the 'Today' programme.
Robert Winston Labour peer is the only celebrity backer of the No campaign so far.
Ken Clarke A Europhile he may be, but he's no fan of Continental electoral methods.
William Hague The first senior member of the Government to speak out against AV.
David Blunkett Would not like to see a Lib/Lab pact even if it got rid of the Tories.
Clegg's Yes camp
Helena Bonham Carter Backs AV but main campaigning focus is for an Oscar.
Colin Firth Withdrew his support for Lib Dems but still supports the party's policy.
Joanna Lumley Star of Absolutely Fabulous who won plaudits for her Gurkha campaign.
Tony Robinson The Yes supporters will hope that he will bring more than a cunning plan.
John Cleese Long-time Lib Dems supporter who could have big role in campaign.
Stephen Fry Will be hoping his army of Twitter followers will, well, follow him.
Eddie Izzard One of Labour's celebrity supporters – also backs Ed Miliband on PR.
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