Although only one man knows for certain when the general election is to be held, it is widely assumed by the political media that Alastair will let the Prime Minister know in plenty of time for the Queen to dissolve Parliament. While no one from Downing Street has confirmed the date, it is an axiom Blair aides have done nothing to dispel that 3 May is a red letter day in Tony's diary.
Despite the ongoing Mandelson/Hinduja saga - and the expected publication of a report into it within weeks - Labour's poll lead has held steady and around 15 to 20 per cent. All the evidence is that the party is cruising to another massive win. This election represents Labour's best-ever chance of winning a full second term of office. According to reports in last week's papers, Labour is already campaigning covertly by rigging ministerial diaries to ensure plentiful visits by high-profile figures to marginal seats. The campaign has truly begun.
For the Conservatives, managing expectations has been a crucial element of their recent shadow campaigning. It is unlikely party leader William Hague anticipates becoming premier - one well-known Tory peer is even betting journalists on the size of the second Blair majority.
But if Hague can reduce that majority by 100 seats or so, his party may take the view he has done enough to warrant a second term as leader of the opposition.
Liberal Democrats must enter the coming months with fear. The 1997 election saw the party win its highest tally of commons seats in 60 years, but leader Charles Kennedy's poll ratings have been squeezed. It will be a surprise if Cowley Street is celebrating on election night.
PRWeek will track the campaign as it takes shape. As well as a series of features on aspects of modern campaigning, we will keep you posted on people moves and new tactics deployed by the parties as they struggle for every vote.
With polling company NOP Solutions, we will be publishing exclusive research on key questions facing the nation's decision-makers, while the Diary will record the lighter aspects of the guaranteed media-fest.
The people running the campaigns have a few fraught months ahead. For Labour this now means a committee convened by Chancellor Gordon Brown and up-and-coming Scottish MP Douglas Alexander.
It also means a tough time ahead for the team at party HQ in Millbank tower, led by head of communications Lance Price. The former BBC news reporter moved from Downing Street to Millbank last summer in a job swap with the then PR chief Phil Murphy.
Since taking over, Price has made a number of key changes, including hiring the head of communications at the Institute of Public Policy Research, Jim Godfrey, as senior press officer. The third man at the top of the Millbank PR tree is Steve Bates, chief press officer and a broadcast expert of several years' standing.
The party's communications will be bolstered by the secondment of players in the public affairs industry. People such as David Hill, a director at Bell Pottinger Good Relations and former party communications head, are widely expected to return to the fold. Others, such as Ian Lindsley at The Communications Group and Rebecca Gray at the Alzheimer's Disease Society are also planning to help out.
The Tories have fewer friends in public affairs at the moment - senior lobbying figures surveyed all favour a second Blair term - but with the pounds 5m donation from gambling businessman Stuart Wheeler to splurge, they are unlikely to be short-staffed. Communications director and former Express editor Amanda Platell has come in for some vocal criticism, both from the political press corps and within the Conservatives' Smith Square base.
The personal drama in the Tories' PR department is likely to be as watchable as its public campaign, but spread-betting firms are refusing to give odds on how many days after the election it will be before she quits or is sacked. Her two deputies - former Times man Nick Wood and Andrew Scadding, late of the BBC - are standing in the wings.
The Tories have indicated their intention to do away with daily election press conferences. A spokesman says Hague is keen to get out of London as much as possible. 'We live in a broadcast age and that needs to be reflected in modern campaigning. Broadcasters want something different than the same press conference set every day for a month,' he says.
Would that the Lib Dems could afford such boldness, its new press and broadcasting director Elizabeth Peplow must be thinking. Peplow, who joined last year from Horse and Hound magazine, is the number two to communications director David Walter, though it is Peplow who will run the PR operation, liaising regularly with the party leader's press secretary and ex-House magazine reporter Daisy Sampson.
The final ingredient in the campaign pie is the range of issues to fight over. The parties have now outlined clear divisions on issues such as public services, taxation and Europe.
For three years after 1997, there was little to choose on taxation because Labour was committed to Tory spending plans. Faced with hospitals, schools and the police in crisis, Blair last week addressed the issue and gave voters a stark choice - improved services or lower taxes.
The Tories are hammering home the message that they are for low taxes, damning Labour stealth tax rises, and presenting a 'moral case' for low tax. This is music to voters' ears, but as well as failing to pinpoint where the multi-billion pound tax cuts will come from, Hague is vulnerable to claims that he cannot improve public services at the same time.
The debate on Europe boils down to adoption of the Euro and has emerged as a significant PR battleground since Blair last week promised a referendum within two years of the election.
Labour has to work out how to communicate its policy - joining if five key economic tests are met - while the Tories attack the tests as a bureaucratic fudge. More fundamentally, Blair has to sell the euro, when the party would much rather discuss the recent interest rate cut and continually booming economy.
With the exception of party grandees such as former Chancellor Ken Clarke and former Deputy Prime Minister Michael Heseltine, an increasingly right-wing Tory party has rallied round Hague's Keep the Pound stance. Simple in conception, this is easy to communicate, with traditional Tory rhetoric appealing both to those who consider the UK would lose out economically in the euro and those concerned with a dilution of national identity.
Backed by a broadly Eurosceptic press, the Tories have most to gain by forcing Europe up the election agenda.
In sum, the best the Conservatives can do is to dent Labour's majority by 100 seats. The best Labour can hope for is to retain half of those it gained last time. It seems a forgone conclusion that Blair will be returned, albeit with a smaller mandate than before.
Additional reporting by Ian Hall
INTRODUCING THE PRWEEK PUNDITS
Charles Lewington ... former Tory director of communications
Charles Lewington is the founder of Media Strategy, a communications firm with clients in retail financial services, transport, healthcare and local government. The agency was established with the help of public affairs shop GJW after the 1997 general election, in which Lewington served as director of communications for the Tories.
An economics graduate and news journalist by training, Lewington's early career took him to the highest levels in Fleet Street. He was associate editor of the Sunday Express before becoming press secretary to John Major in 1995. In that role he was responsible for strategy, advertising, press relations, party conferences and general election planning.
An occasional broadcaster and public speaker, Lewington also contributes to newspaper opinion and media pages. He was awarded the OBE in 1997.
Joy Johnson ... former Labour director of communications
Joy Johnson's career spanned 15 years in broadcast journalism, first with ITN and then as the BBC's political news editor. Her editorship of the live programming at political party conferences was described by commentators as 'breaking new ground in political coverage'.
Before the 1997 election Johnson became director of communications and campaigns for new Labour, and established a 'news driven and story-led' strategy.
On leaving Labour following a cooling in relations with some senior party strategists, Johnson went back into broadcasting - producing programmes on devolution - and lecturing in politics and journalism.
Johnson is an external examiner for Stirling University's post-graduate PR course. She joined the London board of GPC last year, specialising in strategic communications.
Jeremy Browne ... former LibDem director of press and broadcasting
Jeremy Browne spent three years as the Liberal Democrats' press and broadcasting director, working the Westminster lobby, briefing MPs and devising strategies. He covered the resignation of party leader Paddy Ashdown and the election of Charles Kennedy.
Browne's cameo roles in public life include being the defeated Lib Dem candidate in the 1997 election for Enfield Southgate, the seat snatched from Tory incumbent Michael Portillo by Labour's Stephen Twigg.
After a year as president of Nottingham University students' union, Browne became researcher to Lib Dem deputy leader Alan Beith MP. He also served as chief press officer in the 1994 Eastleigh by-election, when the Lib Dems overturned a massive Tory majority to install David Chidgey as the new MP.
Browne is now a consultant at Edelman PR Worldwide.
PREDICTIONS FROM THE PUBLIC AFFAIRS SECTOR
These people earn a living trading on their political nous, so PRWeek put that nous to the test. In the second week of May,we shall hand out a bottle of champagne to the provider of the nearest guess
Adele Biss ... chairman, AS Biss & Co
'There will be fewer women MPs after May. The crunchy numbers question comes with the election after next.'
Labour majority 93
John Arnold ... director, PoliticsDirect.com
'I agree with Westminster's most reliable political barometer - the cabbie. Labour will walk it.'
Labour majority 92
Anita McErlean ... director of communications, Airtours
'The Tories are gaining but it remains to be seen if they can articulate and substantiate their policies clearly.'
Labour majority 90
Jon McLeod ... senior director, Weber Shandwick Worldwide
'I share the view of Tory donor Stuart Wheeler's betting firm - Labour with a huge majority.'
Labour majority 134
Gill Morris ... managing director, Connect Public Affairs
'I lost my job in the fallout in 1987 and am a pessimist. The big fear is low turnout which could cost Labour dear.'
Labour majority 73.