Stefanos Kasselakis was virtually unknown in Greece just six months ago when he was a no-chance election candidate with Syriza, the country’s main opposition party.
These days, thanks to an electoral drubbing of that party, a meteoric ascent fueled by a skillful social media campaign, his status as a former Goldman Sachs trader and a gay politician, along with his movie-star looks, he is seemingly all anyone in Greece can talk about.
Improbably, he is now the leader of Syriza, having essentially come out of nowhere to defeat a former minister for the top role a month ago. But his leadership has sent the leftist party into a tailspin, and is expected to result in one influential faction breaking away at a top-level party meeting this weekend. It has also signaled both a reorganization of leftist politics in Greece and, some analysts say, a shift in the style of the country’s politics to rely more on appearances and less on substance.
“His election is the product of the rightward drift of the previous leadership,” said Seraphim Seferiades, a professor of politics and history at Panteion University in Athens, who pointed to a similar trend across Europe and beyond where the left has strayed from some of its core principles to gain broader appeal.
“Kasselakis is a prime example of this trend, the main idea being that the adoption of sheer imagery — not just gay, but also young and energetic — will do the trick,” Mr. Seferiades added. “Well, it won’t. It will exacerbate the crisis within Syriza.”
A 35-year-old former Goldman Sachs trader who took over a party that just a decade ago blamed the global financial system for devastating Greece’s economy, Mr. Kasselakis lived for 20 years in the United States, including in Miami and New York, before breaking into politics in his homeland. He is Greece’s first openly gay party leader, and recently wed his long-term partner, an American emergency-room nurse, in Brooklyn while pressing for the legalization of same-sex marriage in Greece.
Greek television channels have lapped it up, covering his trips to the gym with his partner and the couple’s walks with their dog, Farlie, as much as his political speeches. (The newlyweds’ Cartier rings were a recent focus of discussion.) But the obsession with Mr. Kasselakis’ personal life has vexed party stalwarts.
Last month, five of its prominent politicians defected within a few days, several other high-profile stalwarts have since signaled their intention to leave, and a document signed by 1,300 party members that was made public on Thursday accused Mr. Kasselakis of “bullying and insolence” for trying to eject critics and moving the party away from the left. Other prominent members have referred to a “state of emergency” and “toxic climate” in the party before a meeting of its central committee this weekend.
Stelios Kouloglou, a member of the European Parliament with Syriza since 2015, last month decided to go independent rather than remain in a party that he said “has become a Netflix series.”
Mr. Kasselakis has defended himself against accusations of arrogance, saying from the outset that the public put him where he is. “I’m not a phenomenon — I’m the voice of a society,” he declared after his victory in late September.
On Friday, he pledged in a video statement posted on the social media platform X not to “betray” those who had voted for him to change the party. “I won’t back down,” he said, adding that he would ask Syriza’s central committee to approve a referendum by party members on the dismissal of four party stalwarts who he said had “brutally offended” him and the party. One of the four quit shortly after the video was released.
Mr. Kasselakis did not respond to requests for comment on Friday.
He was basically unknown before May, when — still a resident of Miami — he stood as an “at large” candidate on Syriza’s ticket in Greece’s general elections. Although that endeavor was bound to fail, given his low ranking on the ballot, it nonetheless set the scene for the next one, when Syriza’s one-time firebrand leader, Alexis Tsipras, resigned after the party suffered an electoral crush by the conservative New Democracy party of Prime Minister Kyriakos Mitsotakis.
In a July opinion essay, Mr. Kasselakis outlined his vision for a Greek version of the United States’ Democratic Party, which he has supported with donations and as a volunteer for Joseph R. Biden Jr.’s 2008 presidential bid. Then, in a frank campaign video, he threw his hat into the ring for the Syriza leadership.
He told of a comfortable upbringing in one of the Greek capital’s most affluent suburbs followed by a relocation to the United States at age 14 when his father’s shipping business collapsed, of a three-year stint at Goldman Sachs and the creation of his own shipping firm.
He promised tax relief for workers, a separation of Greece’s powerful Orthodox Church from the state and the abolition of compulsory military service.
When critics took aim at him over his policy pledges, which were thin on detail, over his banking background and over old articles in which he criticized Mr. Tsipras and praised Mr. Mitsotakis, he hit back with snappy videos saying that he had become a leftist after witnessing the inequalities sown by the banking system.
Mr. Kasselakis’ sexual orientation also became a talking point in a society that remains one of Europe’s most socially conservative. He reported being swamped by hate mail during his campaign, and his expression of a wish to have two sons via surrogacy fueled a furor, including a homophobic rant by a prominent mayor that is now the subject of a Supreme Court investigation.
Despite all of the media exposure, many still wonder what he stands for, apparently confused by his banking background and the fact that he is backed both by close aides to his predecessor and disaffected Syriza supporters eager for change.
Only 6 percent of 1,100 respondents to a recent poll said they viewed him as leftist, with 14 percent regarding him as right-wing. Another poll, of about 1,300 people, found that only 16 percent viewed him positively.
“This blur and contradictory identity, the lack of solid political content and discourse, as well as the fact that he had no attachment to the radical left whatsoever is what prevents him from attracting public opinion,” said Lamprini Rori, a professor of political analysis at the University of Athens.
Mr. Kasselakis’ ascent has come at an unsettled time in Greek politics. Despite Mr. Mitsotakis’ resounding electoral victory, local elections last month suggested that his family’s grip on power might be loosening, given that his nephew was unseated as mayor of Athens amid broader losses for New Democracy.
The Syriza leader rushed to herald “the first major crack in the Mitsotakis regime.” But with New Democracy still holding a comfortable majority in Parliament and Syriza polling below 13 percent, that appears to be wishful thinking.
Some have attributed Mr. Kasselakis’ rise to a protest vote by disgruntled Syriza supporters desperate for new blood. But whether he is a force for renewal or a catalyst for the end of a party in crisis remains to be seen.
“Kasselakis must be a unique case in the global history of politics,” said Thodoris Georgakopoulos, a prominent commentator. “There have been many cases of nonpolitical celebrities cashing in their fame to gain political power. This is not such a case. The members of a political party voted a random stranger to lead it. It is beyond bizarre.”