MPs will make history today when they vote for the chairmen of influential House of Commons select committees.
The coveted posts will be elected through a secret ballot for the first time after reforms were brought in to reduce parliamentary patronage.
Taking charge of a select committee gives backbenchers the opportunity to grill ministers and officials in extended evidence sessions and to draw up detailed reports which help shape the political agenda. They also receive a pay supplement of nearly £15,000.
The secret ballots were a key change proposed by a special committee set up to strengthen the Commons in the wake of last year's expenses scandal.
Previously chairmen have emerged from a behind-the-scenes process that was heavily influenced by party whips.
The jobs will still be shared out between the parties to reflect their strength in the Commons, with Labour taking the key Public Accounts Committee, which acts as Westminster's spending watchdog and is always headed by a senior MP from the main opposition party.
Several MPs have already been installed after being nominated unopposed last night.
Tory John Whittingdale stays on as chairman of the Culture, Media and Sport Committee.
Lib Dems Malcolm Bruce and Sir Alan Beith retain their roles on the International Development and Justice committees respectively, while Labour MP Louise Ellman hangs on to Transport.
Conservative Laurence Robertson takes over as chairman of the Northern Ireland Affairs Committee, Labour's Ian Davidson is installed at Scottish Affairs, and Tory David TC Davies at Welsh Affairs. Greg Knight was unopposed for the Procedure Committee.
The rest face a ballot conducted under the "alternative vote" system - with MPs ranking their choices by number and victory going to the first to get more than 50% of votes. All MPs will be able to vote on every position, but will be presented with contenders for each post from only one party.
The most fiercely-fought battle looks set to be over the leadership of the Public Accounts Committee, with declared candidates including former ministers Margaret Hodge, Michael Meacher and Iain Wright as well as long-serving backbenchers Hugh Bayley and Brian Donohoe.
Tories Michael Fallon and Andrew Tyrie will fight it out to head the influential Treasury Select Committee.
Labour has also secured the chair of the Business Committee, which will be a contest between former education committee chairman Barry Sheerman and backbenchers Adrian Bailey and Geraint Davies.
Graham Allen, Hywel Francis and Fiona Mactaggart will compete for the Political and Constitutional Reform Committee.
And the party will provide the head of the Home Affairs Committee, where former chairman Keith Vaz faces a challenge from ex-minister Alun Michael.
Sir John Stanley, who was senior Tory on the Foreign Affairs Committee in the last Parliament, is now seeking its chairmanship, against the opposition of John Baron and Richard Ottaway.
Some MPs with experience of ministerial office are now hoping to exert influence in the same fields where they once held decision-making power.
Stephen Dorrell, who was health secretary in John Major's administration, is now vying for the chairmanship of the Health Committee with fellow Conservatives Sir Paul Beresford, Peter Bone and Nadine Dorries.
Labour's former local government minister Nick Raynsford is hoping to be named chairman of the Communities and Local Government Committee over ex-Whip Clive Betts.
And former Tory defence minister James Arbuthnot is seeking the chairmanship of the Defence Committee, along with the party's one-time homeland security spokesman Patrick Mercer, eurosceptic Douglas Carswell and Julian Lewis.
Although committee chairs are normally selected from among Westminster's more experienced backbenchers, at least one newly-elected MP is standing.
Neil Parish, who became Tory MP for Tiverton and Honiton last month, is taking on fellow Tories James Gray, Stewart Jackson and Anne McIntosh for the chairmanship of the Environment, Food and Rural Affairs Committee.
Other committees allocated to Labour include Work and Pensions (declared candidates Anne Begg and Karen Buck), Environmental Audit (Barry Gardiner, Joan Walley), and Science and Technology (Graham Stringer, Andrew Miller).
Tory chairmen will be chosen for the Children, Schools and Families Committee (declared candidates Lee Scott, Graham Stuart, Andrew Turner and Rob Wilson), Public Administration (Christopher Chope, Bernard Jenkin, Ian Liddell-Grainger).
Mr Tyrie said the election of chairmen could be a "transformational" moment and the start of wider reforms of committees.
He told BBC Radio 4's Today programme: "They should be more outward looking. They should start to demand more of the powers American congressional committees have.
"I think this will be a transformational moment. The chamber has totally failed to hold governments to account. It's got to be the select committee corridor that does the job."
But he cautioned: "Don't expect something overnight to look very different."Reuse content