MILAN (AP) — Elly Schlein, a 37-year-old U.S.-Italian national and longtime left-wing political operative who worked on two presidential campaigns for former U.S. President Barack Obama, defied polls to become the first woman to head Italy’s opposition Democratic Party.

Schlein’s surprise victory Sunday over the popular governor of Emilia-Romagna, a traditional left-wing stronghold, is attributed to support from women and youth in the rank-and-file, while the party apparatus largely supported Stefano Bonaccini.

Schlein claimed 54% of the vote to Bonaccini’s 46%.

“We will be a big problem” for Premier Giorgia Meloni, Schlein said to supporters, pledging to help the most vulnerable and shore up the labor market with better-paying, secure jobs.

Schlein took an immediate swipe at Meloni for her far-right government’s anti-migration policies, saying that the shipwreck deaths Sunday of dozens off southern Italy “weighs on the conscience of those who only weeks ago approved a decree whose only goal is to hinder rescues at sea.”

Schlein called instead for a system that allows migrants to legally apply for entry into all European nations and for the EU to invigorate its humanitarian search-and-rescue mission.

Schlein takes over a badly splintered party that failed miserably to mount a credible campaign against Meloni in last fall’s elections, leading the PD’s former leader to step down.

Schlein, who grew up in Switzerland with an Italian mother and American father, quit the center-left Democratic Party in 2015 over differences in the direction it was taking under then-Premier Matteo Renzi. She helped the Democratic Party campaign last summer as an independent candidate, winning a seat in parliament even as the party badly lost the general election, and became a card-carrying party member just recently to run as its leader.

A former European Parliament deputy, Schlein cut her political organizing chops on two Obama campaigns and has been aligned with the former Greek finance minister Yanis Varoufakis’ pan-European progressive moment DiEM25. She is often compared to U.S. Representative Alexandria Ocasio-Cortez for her social justice advocacy.

Schlein gained national attention three years ago when she played a key role in blocking the right from taking power in her traditionally left-leaning region of Emilia-Romagna, famously confronting League leader Matteo Salvini over his immigration record.

Prior to winning election to parliament, she was vice governor of the region, working with Bonaccini, charged with social equity and environmental policy.