Conservatives and Liberal Democrats have started drawing up secret manifestos for the 2015 election in an attempt to placate backbenchers who fear their leaders are plotting a political merger.
In the first major salvo of an "ideas arms race" between the three main parties, an official Tory policy review, involving backbenchers from all wings of the party, was launched this month, focusing on keystone Conservative issues including the economy, the elderly and law and order.
The Lib Dems are also drawing up a package of policies aimed at upwardly mobile middle earners – dubbed Alarm-Clock Britons – with a view to having a new shopping list of policies to present at the next election.
Meanwhile, the Labour Party will soon launch the first of its clean-slate policy studies, as Ed Miliband seeks to draw a line under the manifesto he wrote last year but which lost his party power.
With both the Tories and Lib Dems losing the state funding paid to opposition parties, and Labour needing to appear to reach beyond traditional party lines, all three have turned to think-tanks for ideas.
Next month, the second annual Think-Tank Clash will be held in London, where some of politics' leading minds compete to persuade a live audience of the merit of their ideas with "no jargon and no rambling".
The Cabinet Office minister, Oliver Letwin, has held talks with think-tanks from across the political spectrum to get input on coalition policy, in a shift away from Cameroon favourites such as Policy Exchange and Reform. Labour strategists are also keen to reach beyond the traditional left-wing stable of the Fabian Society and Institute for Public Policy Research.
A Labour source said Mr Miliband had made a "big, open offer to community organisations, charities and external networks". Outsiders will lead some of Labour's policy reviews, including the possibility of a general leading a defence review, while other areas such as health and transport are likely to hold in-house, inquiry-style hearings. Nick Pearce, of IPPR, said: "We have a once-in-a-generation opportunity to renew progressive ideas."
The centre-left think-tank Demos said the coalition had created "more fertile ground for cross-party ideas".
The flow of former think-tank employees going on to become ministers continues. Experts applaud the trend, claiming MPs are too often shunted into areas they know – and care – little about.
CentreForum, a Lib Dem think-tank, has seen its profile soar since the coalition was formed. The party's Facing the Future programme is now focused on developing policy that will be "more radical" than anything the Tories or Labour offer at the next election.
The Conservative Policy Forum was relaunched last week. "Any policy work we commission in government is an open book that will be seen by both parties in the coalition. That's fine for everything that relates to between now and 2015, but we need to have ideas and policies that the Lib Dems don't know about," one senior source said.
Back-bench MPs will be invited to pull together all the ideas into a final document.
Influential in the Blair government, centre-left social radicals whose time has come again. Founded in 1993.
Income £1.4m. A third from charities and foundations, a quarter from commercial organisations, and a quarter from state bodies.
Revolving door The ex-Labour Treasury minister Kitty Ussher became director in 2010, replacing Richard Reeves, who is a special adviser to Nick Clegg. Former director Tom Bentley advises Australian PM Julia Gillard. A Commission on Assisted Dying is chaired by the former Labour minister Lord Falconer.
Policy hits Scrapping Audit Commission; abolishing Primary Care Trusts; all good schools to become academies; parenting and early years.
Next battle of ideas British culture in the second decade of the 21st century; living in an advanced capitalist society; business and the Big Society.
Centre-right free-marketeers with influence across the political divide, focusing on delivering public services more cheaply. Founded 2002.
Income £1m. Thirty corporate partners – including Aviva, Cable & Wireless, Ernst and Young, GlaxoSmithKline and Nestlé – each give £7,500 a year; other companies sponsor events. Also receives donations from individuals and trusts.
Revolving door Co-founder Nick Herbert is now Tory minister for policing and criminal justice. Director Andrew Haldenby was head of the political section in the Conservative research department. Advisory board includes ex-Labour minister Frank Field and Rupert Darwall, who advised Norman Lamont after David Cameron left.
Policy hits Cutting welfare for middle and higher earners; reducing the £230bn cost of public sector workforce; tax rises to reduce deficit, including broadening VAT.
Next battle of ideas Productivity of the public sector; economic growth, including business regulation, tax and financial services; Big Society; poverty and fairness.
Adam Smith Institute
Champion of privatising public services and favourite of Margaret Thatcher; policy on health and education influenced John Major and Tony Blair. Founded 1977.
Income Not available. Members charged £150 minimum, £500 for companies and institutions, £5,000 for patrons.
Revolving door Alumni include Tory MP John Whittingdale, one-time political secretary to Margaret Thatcher, later minister and now select committee chairman, and Nick Gibb, a Tory education minister.
Policy hits Privatisation; internal markets in health and education; moving departmental functions into executive agencies; curbing quangos; bus deregulation; and tax reduction.
Next battle of ideas Deregulation and tax reduction; revive economy and tackle debt; devolve power to local communities.
The world's first think tank, often plays key role when the left regroups after defeat, targeting inequality and poverty. Founded 1884.
Income £660,000. Members contribute £160,000, plus £265,000 from conferences and events. Research project funding has come from Barrow Cadbury Trust, Joseph Rowntree Foundation and Webb Memorial Trust.
Revolving door George Bernard Shaw, Emmeline Pankhurst, Oscar Wilde and all Labour prime ministers were members. Outgoing chairman Sadiq Khan is Labour's shadow justice secretary. John Denham, the shadow business secretary, is vice-chairman.
Policy hits First advocated the NHS; minimum wage; independence of Bank of England; Child Trust Fund (now axed by coalition).
Next battle of ideas Challenging coalition's claim to progressiveness and fairness while shaping Labour policy.
New Local Government Network
Blairite ideas factory, with close ties to Gordon Brown; now leading debate on devolving power. Founded 1996.
Income Not available. Corporate partners include Atkins, Babcock, CBI, City of London, PricewaterhouseCoopers and Serco. As a small private company, New Local Government Network does not declare its income.
Revolving door Former director Chris Leslie ran Gordon Brown's uncontested Labour leadership contest before returning to the Commons as an MP in 2010. Dan Corry, a former director, served as head of the No 10 policy unit.
Policy hits Call for directly elected mayors led to more than a dozen being set up under Labour.
Next battle of ideas Councils raising local taxes; the balance of power.
Centre for Social Justice
Quiet Man Iain Duncan Smith's side project after being ousted as Tory leader. It is now making a big noise about tackling worklessness, drugs and debt. Founded in 2004.
Income £1m. Companies, trusts, foundations and individual donations. Age UK and the Calouste Gulbenkian Foundation have sponsored studies.
Revolving door Duncan Smith became Work and Pensions Secretary in 2010, but remains the patron. Philippa Stroud, a co-founder, is his special adviser. Another co-founder Tim Montgomerie is editor of the Tory grassroots website ConservativeHome.
Policy hits Making work pay; the universal credit; reduce the couple penalty in the tax credit system; directly elected police commissioners; more powers of discipline for teachers.
Next battle of ideas Tackling poverty; social and economic recovery; stronger families; tackling addiction and personal debt.
Institute for Public Policy Research
Shaped early New Labour, combining an acceptance of markets with social justice. Founded 1988.
Income £2.5m. Funded by trusts, foundations and some public bodies.
Revolving door David Miliband was a research fellow and headed a Commission on Social Justice. James Purnell, ex-Labour cabinet minister, was a research fellow after university and is now chairman of trustees. Director Nick Pearce ran the No 10 policy unit between 2008 and 2010. Lord Mandelson is chairing a project on the future of globalisation.
Policy hits Child Trust Fund; congestion charge; elected mayors; single working age benefit.
Next battle of ideas Localism and devolution; work/life balance; Big Society; reforming public services; globalisation.
Institute for Government
New kid on the coalition block, aiming to improve how Whitehall works. Founded in 2008.
Income £4m. Funded by Gatsby Charitable Foundation, founded by Labour peer Lord Sainsbury.
Revolving door The director, Lord Adonis, was Gordon Brown's transport secretary. Senior fellow Lord Bichard was permanent secretary at the Department for Education. Academic David Halpern, who drew up the IoG's blueprint, now heads No 10's so-called nudge unit.
Policy hits Civil Service's role in hung parliaments; Nick Clegg needing more staff as Deputy Prime Minister; mid-term review of coalition; caution in axing quangos.
Next battle of ideas How Whitehall fulfils coalition's ambitions; public service reform; retaining talent during cuts; the junior coalition party; the Big Society.
Social Market Foundation
John Major's pro-market favourite turned darling of New Labour. Founded in 1989.
Income £700,000. Supporting organisations include the Barrow Cadbury Trust, the Esmée Fairbairn Foundation, Camelot Group and Hewlett Packard.
Revolving door Ex-director Daniel Finkelstein advised John Major and William Hague, now a Times columnist. Philip Collins, ex-director, was a Blair speechwriter. Ian Mulheirn, a former economic adviser at HM Treasury, is the current director.
Policy hits Welfare reform; paying prison operators by results; means-testing child benefit; raising VAT; a ballot system for the allocation of school places.
Next battle of ideas Public service markets; postcode lotteries in services; generational divide as cuts hit young and old.
Launched by David Cameron, the brainchild of "Red Tory" Phillip Blond, to solve social and economic problems between government, business and civil society. Founded 2009.
Income Not available.
Revolving door Blond left Demos due to "political and philosophical differences" before setting up ResPublica. Senior staff include Asheem Singh, a former adviser to Boris Johnson and Nick Hurd, then minister for civil society.
Policy hits Early champion of Big Society; changing policy on abolishing the infrastructure underpinning Child Trust Funds, leading to Junior ISAs.
Next battle of ideas Light-touch industrial policy vs growth; outsourcing vs community ownership; small government vs Big Society; localism vs centralism; Blue Labour vs Old Labour.
First "Lib Dem" think tank thrust into spotlight, focusing on education, economics and liberalism. Founded in 2005.
Income £450,000. Receives £130,000 from corporates, including Babcock International, Bloomberg and BP.
Revolving door Chief executive Chris Nicholson and Anthony Rowlands, a director, have both stood as Lib Dem candidates. Julian Astle, a director, worked at the Foreign Office and Ministry of Defence, also advised Paddy Ashdown on Bosnia.
Policy hits More academies; opening school system up to outside providers; pupil premium; cutting subsidy for university students.
Next battle of ideas Progressive politics in an age of cuts; modernising public services; an increasingly interconnected, globalised world.
Centre-right progressives with big ministerial punch, refreshing centre-right policies on education, health and community cohesion. Founded in 2002.
Income £2.7m: two-thirds comes from individuals and a fifth from corporates.
Revolving door Founded by Nick Boles, now a Tory MP, with Francis Maude, now a Cabinet Office minister. Michael Gove – now Education Secretary – was the first chairman. Director Neil O'Brien led Open Europe. Former director Anthony Browne works as policy director for Boris Johnson.
Policy hits Free schools; pupil premium; universities setting fees; elected police commissioners; social housing right to move.
Next battle of ideas Housing; welfare; further education; rationalising energy and environment policy.
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