Beware those happy, smiley faces as MPs set off on their holidays, particularly those who decide it might be a good idea to be pictured on a “staycation” to impress voters. You know they would rather be in Turkey than Torquay. But this summer no politician worth his or her salt will stray too far from the pager; the party machinery won’t stop grinding simply because the sun comes out. There is too much at stake as we approach the final date at which a general election must take place.

Gordon Brown may have seen off challenges to his premiership, but his position is far from comfortable. Labour trails heavily in the polls and ministers cannot expect any respite over the next three months as unemployment rises and cuts in public sector spending begin to bite. Unions are likely to flex their muscle: disputes over pay and redundancies, such as the one that brought London Underground to a standstill, will intensify. Unpopular legislation, such as Post Office privatisation, will add further complications. Public anger over MPs’ expenses is unlikely to dissipate any time soon; and, fairly or not, the Government has been damaged more than the Tories by this scandal.

Mr Brown faces critical by-elections in the Speaker’s old seat in Glasgow North East, where the SNP will give Labour a fright, and Norwich North, where the incumbent Labour MP Ian Gibson was a casualty of the expenses row. Defeats in both look more than possible. While the current mood is that Mr Brown will indeed fight the election, disastrous poll showings combined with by-election setbacks could reignite the turmoil. Most Labour politicians believe it unlikely that he would face a challenge before the pre-election conference season in September. It is more likely that a Cabinet deputation will tell him it is time to go.

With the help of Simon Lewis. the new director of communications at No 10, Mr Brown will spend the summer trying to stabilise his position with a series of policy launches. He will hope that the green shoots of economic recovery that some are beginning to detect will materialise into substance. If so, the threat to him will go. Then the pressure will grow on David Cameron, who appears to be coasting towards election victory next year, to show more of his programme for government.

The aftermath of the expenses scandal will rumble on. The Government will press on with legislation for an independent regulator for Parliament before the summer recess, but it could hit trouble in the Lords. Dozens of serving MPs are expected to say they are standing down before the next election. Backbench MPs on both sides are fed up — with themselves for making mistakes and with their leaderships for being tough on them. The Tory old guard — moats and all — suspect Mr Cameron of using the row to get rid of them. They feel that there is one rule for them and another for the front-benchers who have been allowed to get away with their blunders after paying back some cash.

Alan Johnson, considered by many to be Mr Brown’s natural successor, will have his credentials put to the test. The new Home Secretary has stated that his priority is to deal with antisocial behaviour. The scale of the task will become apparent with the annual crime figures, expected in mid-July, that could reveal the first impact of the recession on statistics for burglary and muggings. At the Department of Health another leadership contender, Andy Burnham, also has a fullish in-tray. He has to deal with concerns over swine flu, with the number of cases expected to surge at the end of summer, and rows over NHS spending at a time when his department has embarked on a major campaign to improve public health.

Spending cuts also overshadow the rail industry. With Treasury purse strings tightening, a public subsidy of £5 billion a year looks vulnerable. Against that background, the Government will do well to announce progress for two flagship projects that are due to be confirmed: the £16 billion Crossrail project to build twin train tunnels under London, and a high-speed rail link between the capital and Birmingham.

Cost-cutting measures will also be up for discussion at the General Synod in York next month. Even the Church of England cannot be spared, and a vote will be taken on plans to reduce the number of bishops and senior clergy.

In August the focus will turn to education, when results for GCSEs and A levels are published, which will form the basis for the schools league tables. They are certain to reopen the debate about standards and whether exams really have been made easier.

With such inauspicious tidings, is it really possible for the mood of a nation to turn? Of course, an Ashes win would do Mr Brown and Labour a favour. But the last time something like that happened was in 1966, when Harold Wilson’s fortunes were boosted by England’s World Cup win. Since than, sports fans have learnt not to pin their hopes on a national team. And nor should Mr Brown.