SPIJKENISSE, the Netherlands — He wants to end immigration from Muslim countries, tax head scarves and ban the Quran. He is partly of Indonesian heritage, and dyes his hair bright blond. He is omnipresent on social media but lives as a political phantom under police protection, rarely campaigning in person and reportedly sleeping in a different location every night.
He has structured his party so that he is the only official, giving him the liberty to remain, above all things, in complete control, and a provocateur and an uncompromising verbal bomb thrower.
Geert Wilders, far-right icon, is one of Europe’s unusual politicians, not least because he comes from the Netherlands, one of Europe’s most socially liberal countries, with a centuries-long tradition of promoting religious tolerance and welcoming immigrants.
How he and his party fare in the March 15 elections could well signal how the far right will do in pivotal elections in France, Germany and possibly Italy later this year, and ultimately determine the future of the European Union. Mr. Wilders (pronounced VIL-ders) has promised to demand a “Nexit” referendum on whether the Netherlands should follow Britain’s example and leave the union.
“The Netherlands is kind of a bellwether, a lot of trends manifest themselves here first,” said Hans Anker, a Dutch political strategist who has worked both in the Netherlands and the United States.
“I wouldn’t rule out that Wilders could be prime minister,” he added. “This one is fundamentally unpredictable.”
Remarkably, Mr. Wilders, 53, has managed to build a movement despite his infrequent public appearances. Living under threat since the police discovered plots against him in 2004 has turned him into a politician ahead of his time, using the internet and later social media to talk to voters without the filter of journalists.
It has proved a particularly effective means of reaching disillusioned citizens. Other politicians have followed his lead but almost none have done it as effectively, Dutch experts said.
“He’s the most strategic, smartest politician out there,” said Sarah de Lange, a political science professor at the University of Amsterdam. “He’s very skilled. He’s a very good debater. He has media savvy. Internationally, he’s compared to Trump. But with Wilders every tweet is thought through, calculated. With Trump it’s emotional.”
Right now Mr. Wilders’s party looks set to win more seats than any other or to come in second. However, he has historically polled better before elections than he has performed in them. Still, after pollsters underestimated the likelihood of both Brexit and the victory of Donald Trump last year, no one is relying on predictions.
But whether Mr. Wilders’s party wins the most votes, or enters a government, hardly matters. He has already succeeded in one of his main ambitions — to push politics in the Netherlands to the right and make possible a conversation about shutting out immigrants and dismantling the European Union that was unthinkable not long ago.
Mr. Wilders is close ideologically to Marine Le Pen of France, the far-right National Front leader who is set to make it to a runoff in presidential elections this spring. He was also close to Mr. Trump’s campaign, and is sometimes even called the “Dutch Trump,” though he has a far longer political history and as many differences as similarities.
Like Mr. Trump, Mr. Wilders is unafraid to say things in the most direct, divisive, dismissive, and often disparaging and insulting of ways. Similar to Mr. Trump, many of his supporters feel buoyed and relieved that he is giving voice to what they cannot say, or feel they are not supposed to say.
Last week Mr. Wilders delighted in publicly referring to “Moroccan scum” before a gaggle of reporters. He has called the hijab a “useless piece of cloth.” He has been convicted of inciting discrimination and insulting an ethnic group, but was let off without a penalty.
The one time Mr. Wilders was in government, in 2010, he had an informal liaison with the mainstream conservative party’s coalition, but he bolted when it wanted to cut back pension benefits. Those in his parliamentary group are not technically members of his party, allowing Mr. Wilders to entirely control his party’s platform and decision-making.
Being a party of one also allows him to avoid most campaign finance and disclosure rules, leaving the sources of his money murky, though he receives funding from at least one American conservative group.
Mr. Wilders describes himself as an outsider. Yet he is the third-longest-sitting member of the Dutch Parliament and has spent his life in politics since he was about 28.
In recent years, because of the apparent threats against him, Mr. Wilders has become progressively more isolated. He sees his wife once or twice a week and has cut off his brother, who disagrees with him politically, the brother has said in media interviews. He maintains the image of being present through carefully dispensing Twitter posts, videos and television interviews. His rare public appearances guarantee that every time he ventures out he attracts a media circus.
Last week, he suspended his campaign appearances altogether after reports that a member of his police security detail was suspected of leaking his movements to a Dutch-Moroccan criminal gang.
Still, he manages to travel to give speeches outside the Netherlands, including at the Republican convention in Cleveland, where he spoke at the “Milo Yiannopoulos Wake Up Party,” a gathering of lesbians, gays, bisexuals and transgender people for Mr. Trump.
He has also traveled on many occasions to Israel, for which he developed a deep affection after spending months on a kibbutz as a young man. He is described by political compatriots as friendly with Benjamin Netanyahu, the right-wing Israeli prime minister.
Over time, Mr. Wilders’s own positions have hardened, his colleagues said. He arrived in The Hague, the Netherlands, in 1991-92 as a parliamentary assistant in the mainstream conservative party then led by Frits Bolkestein.
Today Mr. Bolkestein likens Mr. Wilders to “the sorcerer’s apprentice,” who, the story goes, uses one of his newly learned spells to enchant a broom into washing the floor for him.
Soon the water is all over, and he realizes that he does not know how to stop the broom. He tries splitting it in two with an ax, but then there are two brooms, then four. “The apprentice can’t stop,” Mr. Bolkestein said.
It is an apt description of Mr. Wilders, who sometimes seems to try to outdo himself more for shock value and to grab attention than for practical effect, particularly on immigration.
“In 2012 his position was no new mosques in the Netherlands; now it is ‘close all the mosques,’ ” said Michiel Servaes, a Labor Party member in Parliament who has served with him. “In 2012 it was limit asylum seekers to 1,000 a year; now it’s ‘no new asylum seekers.’ ”
Yet Mr. Wilders’s stands have brought the mainstream right to advocate strict limits on aid for immigrants and helped spawn new small right-wing parties, all with strong positions against immigration and in support of stricter rules to push immigrants to accept Dutch culture, Mr. Servaes said.
E. C. Hendriks, a political sociologist who is allied with a new far-right party, the Forum for Democracy, says unease with immigration and disillusionment with the European Union are rife. “Certain groups in Dutch society have had trouble integrating,” he said.
Yet immigrants are costly for the Dutch since the country has a generous social welfare system and pays for newcomers’ education, health care, housing and food.