Yanis Varoufakis has returned to the political arena – even if right now his stage is a deserted square outside the European Central Bank in Frankfurt. He and around two dozen comrades have gathered here to campaign on a sunny April afternoon. They're from "Demokratie in Europa," a small German political party which, in turn, is an offshoot of the pan-European Democracy in Europe Movement 2025, or DiEM25 for short.

Varoufakis is tired, he says. There are more than four weeks to go before the European elections at the end of May. He's been campaigning for three months already. This morning he arrived by train from Freiburg in southwestern Germany; tomorrow he'll be in Hamburg in the north. The 58-year-old economics professor is casually dressed in T-shirt and jeans. When he talks about Europe, his tone is serious. He's worried about the future, about the rise in right-wing populism and the lack of solidarity.

"As a staunch European, I protest against what the European institutions are doing. They're creating discontent, and that produces political monsters like Matteo Salvini and the Lega in Italy, the AfD in Germany, or Golden Dawn in Greece." If things carry on like this, Varoufakis fears we could end up with a situation in Europe similar to that of the 1930s. In order to prevent this, DiEM25 is calling for radical changes, including an end to austerity measures, an active environmental policy, and more transparency within the EU.

Varoufakis himself was once a big cheese in Europe. In 2015, he was asked to join the cabinet of Prime Minister Alexis Tsipras as Greece's new finance minister. He was only in office for five months, but achieved a certain prominence in that time, firstly with his rebellious, confident appearances at the height of the Greek debt crisis; secondly because he clashed repeatedly with then-German Finance Minister Wolfgang Schäuble, who was pushing for Greece to adopt rigid austerity policies.

Politics across national borders

And now it's in Germany, of all places, that Yanis Varoufakis is campaigning for a new Europe. He and his comrades want it to be more democratic than it has been in the past.

In the opinion of his fellow party member, Daniela Platsch, Europe is not democratic at all. "Democracy means one person, one vote: The head of a bank in Frankfurt and the employee who cleans his office both have an equal right to have a say in what goes on." Platsch, a 37-year-old economist, wants to go to Brussels to fight for this kind of justice.

The pan-European initiative DiEM25 calls itself "European Spring," and brings together Europeans across national borders. There are political parties in seven countries standing with a unified election manifesto. Daniela Platsch, who's second on the list for Demokratie in Europa, holds both German and Austrian citizenship. In third place is the philosopher Srecko Horvat. He's Croatian. A German heads the list for the initiative's Greek party, MeRa25 – and Varoufakis is standing in Germany. Varoufakis sees this as an important sign that there is no conflict between northern and southern Europe.

However, one of the main reasons why Varoufakis is standing as a candidate in Germany is probably that Germany, unlike Greece, doesn't have a threshold clause. Ever since the debt crisis, the former finance minister has been not been very popular in his homeland. Many Greeks hold him responsible for the threat of "Grexit" in 2015, when Greece almost crashed out of the EU: The assumption is that he wouldn't garner enough support there to clear the country's 3% hurdle for representation.

For a more sustainable economy

Within the European movement, however, Yanis Varoufakis is seen as a bearer of hope. That evening, he presents his audience with his group's environmental manifesto, the "European Green New Deal." It envisages an annual investment of €500 billion ($560 billion) in green energy, infrastructure and innovation, to accelerate the transition to a green economy. This would not be paid for by the EU member states, but by loans from the European Investment Bank, supported by the European Central Bank.

Around two hundred people have come to listen to Varoufakis in a little hall in Frankfurt. Lukasz Droweicke is one of them. The 42-year-old Pole has lived in Germany for a long time. "I think we have common goals, for which we have to seek common political solutions," he says. He's a member of Poland's Partia Razem, which is part of the pan-European movement to which Varoufakis belongs. Droweicke believes it can only benefit from the experience and popularity of someone like Varoufakis.

Resignation is part of the strategy

That evening, the man of the hour meets with applause. Varoufakis is besieged by members of the audience; he signs books and has his photo taken with fans. He certainly won't be greeted with that kind of enthusiasm in Brussels. However, Varoufakis doesn't see himself in the European Parliament, anyway.

If German voters decide to vote for him, he says that he would regard it as a symbolic act, and would resign after few months as an MEP. The main thing he wants to do, he says, is campaign, and drum up support for a new Europe, first in the elections in Greece, and after that in France and Italy. Not, he emphasizes, in order to gain a position or money, but "because this Europe is standing on the edge of the abyss."