At one time, the coal mined in Bergkamen, deep in the heart of Germany's Ruhr valley, was sent across Europe. The industry provided 12,000 jobs and therefore much of the town's livelihood. Today, the mines have given way to the chemical industry, but the transition remains a struggle.

Throughout the large-scale "structural change" - an oft-heard term around here - Bergkamen has held fast to its loyalty to the Social Democrats (SPD), who at the federal level are trying to unseat Chancellor Angela Merkel and her Christian Democrats (CDU) after their 12 years in office.

"The working class and the SPD used to belong together," said pensioner Klaus Petrat, relaxing in the allotment garden he tends to in his hometown.

Like many former mining towns around the world, Bergkamen has seen better days. Now, it's lots of concrete, a tiny, sleepy pedestrian zone, disused mine shafts climbing high into the sky. There is no train station - only cargo passes through on the town's railway tracks - and, at 10.2 percent, unemployment is double the national average.

'A working-class city'

Once upon a time, the success of the SPD - Germany's oldest existing party and one formed with workers' interests in mind - was a given in mining towns. And, even if current polls make it look increasingly unlikely that the party and its candidate for chancellor, Martin Schulz, will defeat Merkel, the SPD does not appear set to lose any ground in Bergkamen, where it has held the majority in local politics for decades. However, that increasingly appears to have less to do with policy than with party loyalty.

The party's success in Bergkamen "has a lot to do with our past, with the sociological structure of the town as a working-class city," SPD Mayor Roland Schäfer said. Long after the coal industry declined in the 1990s, Bergkamen remains a party stronghold because "we have had long-term success in governing this town, dealing with structural change, making the city more beautiful ... and bringing along with us people who might have been CDU voters, through our direct engagement with the community."

Retired miner Volker Wagner expressed a similar view to Schäfer's.

"The SPD always worked closely with us and our union," said Wagner, at 50 years old still easily the youngest member of the Bergkamen Coal Mining History Club, which meets every Wednesday morning at the town's museum. "And we won't forget that in the future."

But even dyed-in-the-wool SPD voters are forced to admit that the days of absolute majority may soon be over.

Not only are the party's numbers down throughout the nation and in Bergkamen's state of North Rhine-Westphalia, where it just lost a major election, but they even sank to 59 percent in the town's most recent election. At its peak, in the 1970s, the SPD enjoyed 66 percent support in Bergkamen.

Wagner said part of the problem was the apparent lack of a "next generation" of SPD voters: "We're almost all pensioners."

Others say the problem goes deeper than local demographics. "At one time, the SPD cared about the little people, but unfortunately that's just not true anymore," the former miner Petrat said.

"They used to come to the pub, ask us what we were worried about," Petrat added. "They don't do anything like that anymore. ... I'll still support the SPD politicians at the local level, but I'm disappointed in them at the federal level."

"The SPD lost its soul in the grand coalition," Petrat said, referring to the party's two recent stints ruling alongside their CDU archrivals.

The Merkel quagmire

Gamze Cavlakli and Kevin Derichs, students who are part of the SPD's youth wing, Jusos, agree that joining the grand coalition was a big problem for their party. But, unlike some other members, the pair are confident in the future of the party and don't agree with its image as a group of old, white, male pensioners.

"Here in our town, the SPD is the only party that is so close to the citizens," Cavlakli told DW. "We're down-to-earth and always available to talk to."

Like members of the history club, Cavlakli and Derichs are confident that Schulz, the former president of the European Parliament, is the right man for the chancellor's seat after the federal elections on September 24.

"I don't understand the magnitude of Merkel's success sometimes," Derichs said. "People complain about some of her political choices or that she doesn't take strong enough stances - and the CDU is still the strongest party in the federal election."

"Maybe the next generation will bring a change," Derichs said. "As everything becomes more global, it's harder to keep living in the past."

Though the SPD may have little to worry about in Bergkamen, Petrat takes a darker view of the party's future and of Schulz in particular.

Summing up the general criticism of a man who clearly outshines Merkel in enthusiasm - though, crucially, not in poll numbers - Petrat asked what Schulz could possibly know about running the country after so many years working at the European level and so far removed from the "everyday German."

At this, his wife, Anja, sighs. "All politicians make promises and then don't keep them," she said. "We'll vote SPD because, well, who else would we vote for?"