"When you have this much wealth, you can aspire to higher ideals," says a woman pushing her small daughter's stroller in the beautiful old city center of Heidelberg in southern Germany. Laughing self-consciously, she acknowledges readily that Heidelberg has earned its reputation as a Green party stronghold. 

Cosmopolitan, well-educated, aggressively alternative, idealistic and yes, well-off - this could easily describe both the average citizen of Heidelberg and the average Green party voter.

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Heidelberg, and nearby, similar cities like Freiburg and Tübingen, pride themselves on being "Green" cities in the political and ideological sense. All three lie in the wealthy southwestern state of Baden-Württemberg, which in 2011 appointed Germany's first-ever Green state premier, Winfried Kretschmann. Support remained so high, he was re-elected in 2016.

Here in Heidelberg, the Greens poll at about 20 percent support, more than double the party's national average of 8 percent.

A party of personalities

"This is a city open to dialogue… It doesn't matter where you come from, but where you're going!" says Dr. Franziska Brantner, Heidelberg's representative in the Bundestag.

The Greens have not only the richest but also the best-educated voters in Germany, along with the business-friendly Free Democrats (FDP). But though they may be the party of the intellectual elite, more concerned perhaps with the people in Darfur than Duisburg in Germany's rust belt, their enthusiasm is not disingenuous.

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Confident and charismatic as she opens an exhibition of photographs from Iran, Brantner can talk about her accomplishments without appearing arrogant and her dreams of seeing a Green chancellor in Berlin without sounding laughably optimistic.

The crowd at the exhibit cuts across all age groups and skin colors. At the end of the introduction, they pose thoughtful questions to the Iranian curator who has brought the photographs to Germany, showcasing young women from her home country and their dreams for the future.

Aggressive optimism

This kind of authentic, if ever so slightly paternalistic, interest and engagement is at the core of both Heidelberg's character and Green party politics. A day after stopping by the exhibition, Brantner joined her competitors from Germany's other major political parties for a "speed dating" political discussion event at a local school.

After a disastrous showing in the 2013 Bundestag elections, when a demand for tax increases cost them their own clientele, the Greens are focusing on the next generation - promoting more alternatives in education and correcting the gender pay gap.

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This kind of engagement is perhaps best showcased by the Campus Grüne, a university organization that so embodies the intensely oppositional spirit of the Greens that they refuse to officially align themselves with the parent party. These are the true heirs of the founding principles in the 1980s, when the party cultivated a culture of civil disobedience to campaign against nuclear weapons and promote the legalization of cannabis.

Campus Grüne won't formally take ownership of the Green party "because we disagree with several policies of the state government, like university fees for non-EU students," says leader Antje Popp as she and her companions brave the driving rain to pass out flyers encouraging students to get out and vote in September.

Now that they are in power in Baden-Württemberg, albeit with conservative junior coalition partners, the Christian Democrats (CDU), it must indeed be difficult for the Greens to stick to their roots in the home state of Mercedes and Porsche.

"I don't think they should be in government, to be frank," says Jörg, an academic in his 30s who grew up in Heidelberg. "I vote for them, even if some of their positions are out-of-touch or have been taken over by other parties, because I think issues like animal cruelty and alternative energy should be discussed in parliament. But I like them better as an opposition force."

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A place above politics

But Jörg, like many others in Heidelberg, would rather talk about his city's stellar reputation for taking care of refugees and as a destination for international guests than politics. It seems that in Heidelberg, politics is a vulgar subject, unsuited to polite conversation.

These sentiments were echoed by Christiane Link, manager of the highly successful artisanal organic bakery called Mahlzahn, founded by a collective of Green party members more than three decades ago.

"We have a large university, a very enlightened population in Heidelberg," said Link, a sensible-looking woman in her 50s. She admitted that her type of bakery would probably not enjoy the same amount of success in industrial neighbor Mannheim or out in the country. But when it came to the political leanings of her clientele, Link steadfastly declined to offer an opinion.

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Perhaps the attitude of Heidelbergers was best summed up by Uwe Hollmichel: "It's not about people. It's about politics!"

A banker by trade, Hollmichel spends his free time as the volunteer leader of a local youth sports club, which runs the "Weltliga" soccer tournament. The Weltliga, which boasted hundreds of young refugee members during the height of the crisis in 2015, has seen its numbers dwindle to 30 or 40 as most have gotten jobs, apprenticeships or university spots. 

Although the Greens may be the smallest opposition in the Bundestag now, it would seem they have nothing to worry about in Heidelberg, where party loyalty characteristic of much older parties will likely carry them to victory, at least here, come September.