He is a recovering alcoholic who dropped out of high school and spent most of his political career abroad.
So when Martin Schulz returned home to Germany with the goal of unseating Chancellor Angela Merkel, perhaps the world's most powerful woman, it was understandably viewed as a suicide mission.
Merkel had made mincemeat out of the last three challengers from Schulz's Social Democratic Party, and there was little doubt that she could do so again.
But in an era when voters worldwide seem prepared to throw off the establishment and take a chance with an untested populist, Schulz, a jovial former bookshop owner from Germany's Rhineland region who until recently was president of the European Parliament, has quickly been embraced as a serious challenger.
In just two weeks since taking over his party's leadership, Schulz has shattered the conventional wisdom that he and his party have no chance and has given the Social Democrats their first lead in polls over the conservatives since 2006.
After Britain's unexpected vote to leave the European Union and Donald Trump's against-long-odds victory in the U.S. presidential election, the Social Democrats' rally in opinion polls has raised serious doubts about whether Merkel can win a fourth term.
Her reelection was once seen so certain that even then-President Obama unexpectedly weighed in late last year, telling German voters on a visit to Berlin that if he could vote here, he would vote for Merkel. It was an unprecedented intervention on behalf of the conservative party leader — and an astonishing affront to the party that is Germany's closest equivalent to Obama's Democrats.
The German election is suddenly an open contest, according to opinion polls.
The Social Democratic Party (SPD), which last beat Merkel's center-right party outright in 1998 and lost control of the government to her party in 2005, has surged eight percentage points to 31% in the last two weeks after years of stagnating just above 20%, according to a poll by the INSA institute for Bild newspaper. Meanwhile, the conservative bloc, consisting of Merkel's Christian Democrats and their Bavarian sister party, the Christian Social Union, fell from 33% to 30%.
"It's caught everyone by surprise that Schulz was able to help the SPD make such a powerful break out of the doldrums they'd been trapped in for such a long time," said Thorsten Hasche, a political scientist at Goettingen University. "The lesson learned is that he has proven what was until recently not thought possible: that the right candidate on the left can unify the party and mobilize the masses."
The Social Democrats' sudden strength in polls is no guarantee of success in the Sept. 24 election, in which Merkel appears to have more coalition options. In Germany's complex multi-party system, it will most likely take a two- or even-three party alliance to form the next government.
The Social Democrats would like to create a left-of-center government with the Greens and Left parties. Until recently, its only path to power was seen as being a junior partner in another "grand coalition" with Merkel's party. Schulz's surge has suddenly given his party a number of more palatable left-of-center options and even the chance to lead the next government.
"Schulz has managed to mobilize a lot of previously undecided voters and people on the left who had turned their backs on the SPD," said Nils Diederich, a political scientist at Berlin's Free University. "There's a lot of hope vested in Schulz right now. But I'm not sure yet if it's just a lot of hype that will fade away by the election."
In a country where frustration over professional politicians with fancy university degrees is growing, Schulz offers a more humble and straight-talking approach. He appears to be wooing back some supporters who abandoned the party 14 years ago when it agreed to tough, pro-business labor reforms and pension changes that hurt the working class.
"We've suffered for a long time in the polls, and now we've got something to cheer about," Schulz told reporters on the campaign trail this week. "It confirms what we suspected all along, that people want an SPD government."
Pollsters admit they were surprised by the scope of the party's gains but aren't sure whether they will last.
"Schulz is certainly attractive for the 'little people' because he understands what the working class voters are going through — they sense that he's one of them," said Peter Matuschek, a senior pollster at the Forsa institute in Berlin. "If you look at his resume, he's one of them: no high school diploma and no degree."
As a young man, Schulz had wanted to be a professional soccer player, but his career was cut short by injury, leading to his bout with alcohol in the 1970s. Matuschek said he doesn't think that past will hurt him politically — on the contrary, it might help him among voters who see someone "who made it back after hitting rock bottom." After he quit drinking, he became more and more involved in politics, becoming his town's mayor at 31.
His unvarnished way of speaking has touched a nerve, especially among the country's legions of working-class voters who had abandoned the Social Democrats in droves when the party's last chancellor, Gerhard Schroeder, pushed it from the left into the political center from 1998 to 2005.
"It's time for a change," said Miriam Dieter, a Berlin student. "The others talk a lot without saying anything. Schulz is different. He talks directly about what's on people's minds."
In one talk show interview, Schulz deftly zeroed in on Merkel's biggest weakness: her party ally Horst Seehofer, the leader of the Christian Social Union (CSU) in Bavaria, who has attacked her relentlessly for refusing to introduce an upper annual limit of 200,000 on the number of refugees coming into Germany.
The Social Democrats have generally taken a pro-refugee position while Merkel's conservatives remain badly split on the issue: Merkel and her Christian Democrats (CDU) are for allowing in refugees while the Bavarian party is opposed.
Still, the question of refugees is not expected to play a major role in the campaign. Neither Merkel's conservatives nor the Social Democrats have any interest in putting a spotlight on the arrival of more than 1 million people seeking asylum from wars and turmoil in the Middle East and elsewhere.
Polls show a shrinking majority of Germans continue to support Merkel's policies of opening the country's gates to refugees. But her position is far more controversial among conservatives than among Social Democrats .
"If the CDU and CSU continue to fight about the number of refugees and don't get their act together on that fast, it will hurt them massively in the fall election," said Matuschek at Forsa. "The SPD under Schulz have a unified position supporting refugees. The conservatives don't."
Kirschbaum is a special correspondent.