Earlier this month some of the most influential thinkers of the Labour movement were summoned to a secret meeting at Downing Street to discuss how to make Britain more “family friendly”.

Ministers were concerned that the Tories were stealing a march with eye-catching policies on marriage, parental leave and childcare. In the crucial electoral battleground of young mothers and fathers, Labour was falling behind and something needed to be done.

It was not lost on those present that the No 10 meeting had been scheduled for 8am — a time when many parents would normally be setting off on the school run. The seminar’s host, Yvette Cooper, the work and pensions secretary, made a joke of it: “Who decided to hold a seminar on work-life balance at breakfast time?”

The assembled think tank heads and Downing Street apparatchiks cantered through some of the issues that inflame the passions of parents of young children.

Then the subject of childcare vouchers came up. Gordon Brown recently announced the abolition of this perk worth up to £2,400 a year for working parents. One after another, people stood up and said why he had been wrong to do so.

“It is dreadful politics,” said one Labour candidate. “These vouchers are good on the doorstep. They are easily understood. They benefit working parents and they are popular.”

Last week the issue spilled out into the open as nine former Labour ministers signed a letter warning that abolishing the vouchers, used by 350,000 parents, would “remove support for working parents and for businesses in key marginal constituencies”.

It was the latest skirmish in the battle for the “Mum’n’Dad vote” — the successors to Worcester woman and Mondeo man, the emblematic electors who helped propel Labour into government in 1997.

Why have both Tory and Labour strategists identified this demographic group of parents as the key to the general election? Which party will win this political struggle for control of the school gates and the playgrounds?

THE key point about young parents is that there are more of them than there used to be. The “echo-boom” generation — the children of the post-war baby boomers — are now reaching their mid-twenties and thirties and starting to have their own children.

Importantly for the politicians, young married parents are more likely to vote than their childless friends. Two-thirds of married 18 to 34-year-olds voted in the 2005 election, compared with 52% of single people in the same age bracket.

These younger voters tend not to have fixed, tribal views on politics and are more likely to vote purely for the party that offers the best menu of policies for them and their families.

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