“We have not used up all of our ideas and visions for the future of our country within the bounds of a coalition agreement that expires in 2021,” Ms. Nahles told party delegates, referring to the Social Democrats’ recent decision to enter another government under Ms. Merkel. “We need a debate about the future that goes far beyond that which we hammered out with the conservatives and the place for that is within our party.”
Ms. Nahles was elected with 66 percent of the vote, easily defeating her only challenger, Simone Lange, mayor of the northern city of Flensburg, who jumped into the leadership race on the premise that true change could come only through new faces.
The victory for Ms. Nahles marks the first time the Social Democrats have elected a woman as their leader — a role Ms. Merkel has had for the Christian Democrats since 2000. Despite the historical backing Ms. Nahles received from her party, however, many of the voters she is hoping to win over appear to be more skeptical about her ability to turn things around.
Only 33 percent of Germans expressed confidence that she could pull the party out of its slide, while another 47 percent said they did not believe she was up to the challenge, according to a survey before her election by the public broadcaster ARD.
Lars Klingbeil, the party’s secretary general, said that her position as leader of the Social Democrats’ parliamentary caucus, but not a member of the government, placed her in a position to “strengthen the party’s independent profile and put a Social Democratic stamp on new laws.”
“Those who know her know she’s not afraid to rub people the wrong way, but she is also very decisive,” Mr. Klingbeil told reporters last week.
That independence appears to be crucial to the survival of a party that was widely abandoned in last year’s election. Many voters could no longer distinguish between the center-left party, born out of the workers’ movement at the dawn of the Industrial Revolution, and the conservative Christian Democrats, who have held the chancellery under Ms. Merkel since 2005.
Ms. Nahles founded a local chapter of the Social Democrats in her hometown, Weiler, in the western German state of Rhineland-Palatinate, while still in high school. In 1995, she became the national leader of the Social Democrats’ youth wing, storming on to the national stage by denouncing the leadership as neoconservatives who were endangering the party’s traditional left-wing, working-class roots in a speech that shook up the party congress.
Even as she rose through the party ranks, becoming a member of Parliament for one term in 1998, then returning again in 2005, she has remained true to her penchant for direct remarks, even when behind a podium, and for championing the working class.
In 2013, as a member of the opposition, she called out Ms. Merkel’s government for stagnation and for a lack of innovation, taking to the floor of Parliament and singing a verse of the theme song from the television show “Pippi Longstocking,” a dig at what she saw as the government’s efforts to pretend everything was going well, despite evidence to the contrary.
Later that year, her party returned to government, again under Ms. Merkel, and she became labor minister. During her tenure, she pushed through a minimum wage, breaking a longstanding tradition of allowing unions and company leaders to hammer out individual guidelines for each industry. She also succeeded in giving workers the right to retire with full benefits after 45 years of paying into the social security system.
Asked on national television how she felt after her final cabinet meeting in Ms. Merkel’s previous government, she said it had been sad. Then, she swiftly added, “Starting tomorrow, pow — right in the kisser,” referring to how her party would be more combative with the conservatives from then on.
Ms. Nahles has developed a strong network in the Social Democratic Party and, as a former youth leader herself, earned the respect of the party’s critical youth wing, even though its leader, Kevin Kühnert, unsuccessfully campaigned to keep the Social Democrats out of the coalition government. Those links will be an advantage for the task ahead.
“If we are going to write a new party program, we can’t do it with just 150 pages of criticism about what’s gone wrong in the past, but need people who have ideas for the next 20 years,” Mr. Kühnert said. “I think Andrea Nahles is capable of this. She’s really burning to take on this debate.”
In her senior yearbook, Ms. Nahles wrote “housewife or chancellor” as her career goals. That she has spent the past two decades in federal politics, her political allies quip, now leaves her only one option.
But first, she must secure her party’s future.