Pro-EU Britain Stronger in Europe wants young supporters to try to win round older people, who are more likely to vote

These days a referendum campaign group only truly wins its colours when it comes up with a wheeze that is promptly laughed out of court.

The pro-UK Better Together campaign passed with flying colours during the Scottish independence referendum when it was widely mocked for releasing a video featuring a woman who could not make up her mind how to vote.

The pro-EU Britain Stronger in Europe has followed in the footsteps of Better Together by launching a “Talk to Gran” campaign to encourage young voters to try to win round their grandparents to the remain side.

The group, which was formally designated on Wednesday by the Electoral Commission as the main pro-EU campaign group, has designed 14 postcards it hopes supporters will send to their grandparents. Messages on the cards range from: “Nan, I know I should call more but … I want you to know why I’m voting to stay in Europe” to: “Gran, let’s sit down for a cuppa, a slice of Battenberg and … A chat about why my future’s in the EU.”

The campaign is designed to address two of the central weaknesses of the remain side: the need to enthuse younger voters, who are likely to be more pro-EU but who are less likely to vote, and the need to change the minds of older voters who are more likely to be anti-EU and more likely to vote.

Gerry Hassan, the Sunday Mail columnist, tweeted: “#EUref Remain campaign launch ‘Talk to Gran’ campaign. This could be their patronising BT lady moment.”

Will Straw, executive director of Britain Stronger In Europe, said: “We believe that the passion and enthusiasm of young voters can be channelled into getting their older relatives out to vote for Britain to remain in Europe. This referendum will not be won simply by winning the argument in the media, but by creating a bottom-up, word-of-mouth campaign that will reach voters of every age in all parts of our country.

“We have already trialled these postcards at a number of the universities, where they have been shifted like hot cakes. So when young people next share a slice of cake and a cup of tea with their gran, they can tell them proudly that the positive, progressive and patriotic choice is to vote to remain.”