By Elinor Shields
BBC News, Madrid
Sunday's first vote on the European Union charter may be a big day for Brussels, but Juan Pablo has other plans.
Mr Zapatero is not allowed to publicly campaign for a Yes vote
"I'll be having a nice little drink," the Madrid newsagent says. "It doesn't interest me at all."
His stance is Spanish Prime Minister Luis Rodriguez Zapatero's big fear for what is the first of 10 polls in Europe over the next 18 months - abstention, not opposition.
Madrid hopes a strong Yes will send a strong message to other European voters - but some polls predict Spanish turnout will be 40-50%.
To help publicise the vote, the government has turned to stars and gimmicks to stave off the apathy that dogged recent European elections.
Fizz and football
To spread the word, football stars have been signed up to read sections of the treaty on television and radio.
Contestants on a Spanish version of reality TV show Big Brother were also asked to explain bits of the text to each other, reports say.
Football players have been walking out onto the pitches with banners encouraging people to vote.
Millions of free copies of the charter have been handed out at entrances to football stadiums and in Sunday newspapers.
And to add some fizz, Spain's Youth Council has been handing out a referendum drink.
The organisation has been distributing a quarter of a million cans of "Referendum Plus" at university campuses and cinemas.
The drink promises to energise people to vote - "thanks to its stimulating action against fatigue".
'No one explained'
The government has spent about 7m euros to promote the referendum - but it is not yet clear if the publicity will pay off.
Few Spaniards are believed to have read the text of the constitution's 448 articles and up to 90% say they know little of its content, according to a recent government poll.
Esperanza Ramos, 49, says she has read the document because it was handed out in the newspapers.
But another voter, Luis, told BBC News he might abstain because he feels ill-equipped to vote.
"Normally I would vote Yes for the European Union," the 77-year-old said.
"But we are not ready. For me it is a bit of a protest because no one explained it to us."
Lack of debate
Pundits say spreading - and selling - the message to a mass audience are two different things.
"It's very difficult," says Peru Egurbide, diplomatic correspondent for Spanish newspaper El Pais.
"Most people are not interested in European matters. They are listening to general arguments and will vote about general arguments."
Observers also blame the brief campaign period and widespread pro-European sentiment for the lack of debate on - and thus knowledge of - the treaty.
The prime minister is constitutionally forbidden from campaigning on either side, which means the government can publicise the vote, but cannot promote the issue.
Commentators say this rule has also limited debate - as well as prompting allegations of bias.
Spain is likely to vote Yes on Sunday, but for Europe analyst Jose Ignacio Torreblanca, the turnout is key.
"At stake in Spain is the capacity of the political class to convince people that Europe is important," he says.