AMSTERDAM — Jesse Klaver, the dynamic 30-year-old leader of the Dutch green party, has fought his campaign for Wednesday’s election like an American Democrat, shaking the Netherlands’ tradition of low-key electioneering by creating a personality-led mass movement.

If the polls are to be believed, his GreenLeft party will quadruple its number of seats in the lower house, potentially propelling it into a role in the next coalition government.

Yet Klaver’s ambitions don't stop there. As support for the Labor Party plummets, Klaver is positioning himself as the new leader of the left, and even the potential prime minister of a progressive coalition. That might sound preposterous for a party with just four MPs. But Klaver told POLITICO this was a “realistic” prospect.

“The other parties are not gaining momentum, it’s very difficult for them to win elections. I think we’re in a good position to win,” Klaver said, away from a scrum of fans and media at a recent campaign event.

“It’s a reaction to what’s happening in the international sphere. People are afraid of what’s happening with Trump in the United States and Brexit in the U.K. and they’re looking for an alternative. Some hope, some inspiration, and change. That’s what we are.”

"My ambition is to make a government without [current Prime Minister] Mark Rutte," said Klaver. But if the polls are borne out, the left-wing parties together simply won’t have the numbers for that. What’s more likely is that Klaver will find himself invited to shore up a center-right coalition, forced to decide between remaining true to his party’s ideals and entering power for the first time in the party’s history.

Lucky clover

Klaver had his eye on the prize early.

He is an oddly fortuitous figure: aside from his obvious knack for the job, his surname — which means clover, a symbol of luck — has become the motif for the campaign. He became a lawmaker in 2010, aged just 24, and won the party leadership in 2015, announcing immediately that the party's campaign for the 2017 elections had begun.

The campaign strategy was designed by Klaver and Wijnand Duyvendak. The latter's career perfectly sums up the party’s transition. Once a radical activist, he was forced to resign as a lawmaker in 2008 when he admitted he broke into the Ministry of Economic Affairs to steal plans for a nuclear plant in 1980s. Now he leads a campaign self-consciously modeled after those of U.S. Democrats, right down to the software used to organize and communicate with activists: Blue State Digital, a company founded by Barack Obama’s former digital strategist.

"Both Wijnand and Jesse were inspired by the campaigs of Bernie Sanders, Barack Obama and Hillary Clinton. The grassroots way of organizing," said Marjolein Meijer, the party chairwoman. "This needed a translation as the Netherlands is not used to the U.S. style of campaigning ... We needed to start at the very basics."

It was Klaver’s idea to hold “town halls.” At first, these meetings drew fewer than 200 people. Along the way, the name changed to “meetups,” and they grew, first drawing hundreds, then thousands. Previous meetings had only ever been for the party faithful, to discuss policy in detail.

Klaver uses the meetups to talk about his broad political vision, speaking of “hope” “optimism” and “change” in rolled-up shirt sleeves and slacks.

The new, professional style has paid off. Since Klaver became leader, the party has gained 6,459 new members, a third of them aged under 30. Donations almost doubled the party’s initial €500,000 campaign pot. A dedicated team was charged with assigning tasks to new volunteers, to draw them into the movement. Even long-time volunteers were trained in how to go door-to-door canvassing, a new tactic for a party which in the past mostly handed out flyers.

“The greens are known as people with woollen socks, if you know what I mean,” said Detleff Mellies, a 28-year-old graphic and web designer from the northern Netherlands. He joined the party four months ago in response to what he saw as an “uprising of the far right” in his small village.

Within 24 hours of filling out the online form to join the party, Mellies received an invitation to an online instant messaging channel, where volunteers were coordinating what work needed doing. He ended up helping to code the chat bot that responds to queries on the party’s Facebook page.

“I started to realize GreenLeft was actually a serious political party,” Mellies said. The next thing, he was out canvassing in his village.

The Trump effect

When Donald Trump was elected U.S. president in November, it was a confidence boost for the Dutch radical right, which saw in him a likeminded outsider who had swaggered in and upset the system.

Yet Trump was a gift to the greens too. In the 24 hours after his election, 250 people signed up as new GreenLeft members. Party leaders say it had an immediately obvious galvanizing effect.

“I wouldn’t say it was worth it, but it helped,” said Meijer. “It was an influx of people saying: not on my watch.”

Trump is now regularly name-checked in Klaver’s speeches and in campaign material, along with Britain’s vote to leave the European Union and the presidential ambitions of Marine Le Pen in France.

If Klaver pulls off a triumph and increases his party’s seats from four to between 16 and 18, as an average of polls suggest, it will be the party’s best-ever showing.

“This is not just about elections in the Netherlands, but the whole of Europe,” Klaver told the crowd at his final campaign rally this month. “In the Netherlands, we must show that we are going to stop populism, and that there is an alternative.” The crowd cheered.

This grand finale meetup drew an audience of 5,000 to a concert hall in Amsterdam. Another 8,500 watched a livestream of the event on Periscope.

There were long lines for beer. The vegan wraps sold out. Rapper Massih warmed up the crowd with a tune with the refrain “not bad for a refugee." A stall sold Jesse Klaver books and GreenLeft bicycle bells.

“It’s good branding,” said Zoe Birkin, a 22-year-old psychology graduate with a green clover painted on her forehead. “It stands for the green movement, but also hopefulness and luck. It’s idealistic, but as a political movement you need a lot of branding in these times.”

Idealism and political reality may be about to meet for GreenLeft supporters. If Klaver pulls off a triumph and increases his party’s seats from four to between 16 and 18, as an average of polls suggest, it will be the party’s best-ever showing.

But it will also pose a dilemma of whether to go into coalition, as will almost certainly be required, with parties on the right. Time after time, this is a path that has ended in electoral disaster for left-wing parties that have shored up center-right coalitions.

“My main concern is that they would really kill what we’ve built. We’d be stepping into the same grave as the Labor Party,” said Mellies, the new member. “It would be such a shame if we get this movement going and it all falls apart.”