The lack of any discernible ‘Brown bounce’ following the G20 summit, let alone the fallout from the McBride email scandal, leaves Labour facing heavy local election losses on 4 June.

On each of the last three occasions – 1997, 2001 and 2005 – these mainly county council contests have coincided with general election victories, the party’s local fortunes benefiting both from high turnout and the coat-tails of the national leadership. Now, however, time looks to have run out for Labour’s ‘lucky cohort’ of councillors as they brace themselves for their first experience of the mid – or maybe end of – term blues.

Labour will be defending about 500 seats and control of just four of the 34 councils with elections – Derbyshire, Lancashire, Nottinghamshire and Staffordshire. A swing of 6 per cent to the Tories since 2005, well within the margins currently being recorded in opinion polls and local byelections alike, would see up to 200 of these seats and every county slip from the party’s grasp. Lancashire and Staffordshire would move straight to the Tories, with the fate of the Labour minority administration in Cumbria also under severe threat.

Of course the precise swing against Labour will vary from place to place, but results directly against the trend are unlikely given the change in political mood since 2005. This is in contrast to both 2007 (Leicester and Luton) and 2008 (Slough) when Labour did manage to claw councils back amidst a generally poor set of local elections as the impact of the Iraq-influenced contests of four years earlier unwound.

Labour activists may try to take heart from comparing these elections with previous local contests one year out from a general election triumph. In 2000 William Hague led the Tories to 600 net gains on a 38 per cent national equivalent share of the vote; in 2004 Labour limped in in third place behind the Liberal Democrats with a paltry 26 per cent share.

On both those occasions, however, the local results stood in sharp contrast to national polls putting the party ahead. Erstwhile Labour supporters, it seemed, decided to sit on their hands and defer judgement on the government. This year the Tories are well ahead on all measures of opinion. If David Cameron can at least match last year’s 43 per cent share at the locals, he will be precisely where Tony Blair was in 1996 one year before the Labour landslide.

Such an outcome would push Labour losses close to 250 (half of all seats being defended) and there would be huge swathes of the south and Midlands with no Labour elected representatives at all. Across Britain Labour councillors would make up less than one in four of the total as their numbers plummet below 5,000 (in 1997 the party had almost 11,000).

Nor should anybody be fooled if the Tories appear to do less well at the simultaneous European parliament elections. The proportional electoral system tends to make for glacial changes in the distribution of seats and is notorious for encouraging electors to cast cost-free votes for minor parties (remember the Greens’ 15 per cent in 1989 and UKIP’s 16 per cent in 2004). These results will provide a much less reliable guide to the underlying state of British public opinion.

With the Euro poll being counted and declared at local authority level, it will be the local elections, too, that feature in the popular parlour game of totting up the votes in individual parliamentary constituencies. The Tories need a swing from Labour of 4.3 per cent at the general election to become the largest party in a hung House of Commons. Results in constituencies like Lancaster and Fleetwood (8.8 per cent Labour notional majority), Northampton North (8.5 per cent), and Stevenage (8.1 per cent) will provide a useful measure of their progress.

Even more worrying for Labour would be if the Tories are also building majorities in places which they need to win on a 6.9 per cent swing for an overall Commons majority. Local indicators here include Carlisle (13.5 per cent Labour notional majority), Hyndburn (13.8 per cent), and Warwickshire North (15.3 per cent).