Her fans call her Heidi. She is 36 years old. She talks a mile a minute. She has a tattoo of the Polish-German revolutionary Rosa Luxemburg on her left arm and a million followers across TikTok and Instagram. She was relatively unknown in German politics until January, but as of Sunday, she’s a political force.
Heidi Reichinnek is the woman who led the surprise story of Germany’s parliamentary elections on Sunday: an almost overnight resurgence of Die Linke, which translates as “The Left.”
A month ago, Die Linke looked likely to miss the 5 percent voting cutoff needed for parties to earn seats in Germany’s Parliament, the Bundestag. On Sunday, it won nearly 9 percent of the vote and 64 seats in the Bundestag. “It was one of only five parties to win multiple seats in the new Parliament, joining the Christian Democrats, the Social Democrats, the hard-right Alternative for Germany and the Green Party.
It was a remarkable comeback, powered by young voters, high prices, a backlash against conservative politicians, and a social-media-forward message that mixed celebration and defiance.
At a time when German politicians are moving to the right on issues like immigration, and when the Alternative for Germany, or AfD, doubled its vote share from four years ago, Ms. Reichinnek, the party’s co-leader in the Bundestag, and Die Linke succeeded by channeling outrage from liberal, young voters.
They pitched themselves as an aggressive check on a more conservative government, which will almost certainly be led by Friedrich Merz, a businessman who has led the Christian Democrats to take a harsher line on border security and migrants.
Mr. Merz’s ascent, and his decisions in the middle of a campaign that his party led from the start, appear to have helped Ms. Reichinnek. In January, after a deadly knife attack by an immigrant in Bavaria, Mr. Merz pushed the Parliament to vote on a set of migration restrictions that could only pass with votes from the AfD — breaking decades of prohibition in German politics against partnering with parties deemed extreme.
Many analysts trace Die Linke’s surge to Ms. Reichinnek’s furious — for the German Parliament, anyway — speech denouncing Mr. Merz and his measures.
“You just said that no one from your party is reaching out to the AfD!” she shouted, in a speech that has since racked up nearly seven million views on TikTok. “That’s right! They’ve been happily embracing each other for a long time already!”
In the month that followed, she called the AfD a fascist party and demanded that the Christian Democrats fire Mr. Merz. She proposed strengthening immigrants’ rights, increasing pensions and imposing stricter rent controls to help people struggling with postpandemic price increases across Germany.
She also called Die Linke the country’s last great firewall against the far right.
Die Linke coupled those calls with an aggressive social media outreach and party-like atmospheres at its rallies. It added more than 30,000 new members in the last month of the campaign, said Götz Lange, the party’s press officer.
In the campaign’s final week, Ms. Reichinnek traveled to the Berlin suburb of Treptow-Köpenick to talk to Ole Liebl, a queer influencer, about “techno and TikTok.” Afterward there was a party, with a DJ set, including a techno mix with the voice of a famed left leader in Germany, Gregor Gysi.
The venue, an old brewery, was bursting at the seams: Instead of the allowed 400 guests, around 1.200 people showed up. Most of them were techno lovers in black hoodies, people with multicolored hair and T-shirts with “antifa” slogans written on them. They mostly appeared to be in their early 20s.
There wasn’t enough space inside for everyone, so around 800 guests followed the event outside and downstairs, on a livestream. Wearing a rust red-colored sweater and jeans, Mr. Reichinnek appeared after a 30-minute delay, smiling and waving to the crowd.
“Thank you for being here,” she said. “It’s crazy, I don’t even want to know what it looks like down there. If you need help, try banging on the ceiling really loudly, we’ll know.”
The crowd roared.
On Election Day, Die Linke surprised analysts and appeared to snatch votes from the Greens and the Social Democrats, the party of the incumbent chancellor, Olaf Scholz, and got new voters to turn out. In Berlin’s central Mitte neighborhood, it won areas previously dominated by the Greens.
Founded in 2007 and descended from the former ruling party of East Germany, Die Linke had recently been better known for its failures than any success.
Its most well-known leader, Sahra Wagenknecht, quit the party to start her own — which blended some traditional left economic positions with a hard line on migration and an affinity for Russia.
That may have been a blessing, said Sven Leunig, a political scientist at the University of Jena, a public research university in Germany. Ms. Wagenknecht’s positions had split the party. “They were torn,” Mr. Leunig said, and voters did not like it.
The departure also allowed Die Linke to enlist new candidates and leaders. Other mainstream parties continued to push familiar faces and may have paid the price.
Daria Batalov, a 23-year-old nursing student from the central town of Hanau, said she was won over by Ms. Reichinnek’s TikTok videos. “They really spoke to me,” she said, adding, “And it was clear to me after a few videos that, OK, my vote is going to Die Linke.”
Analysts said Ms. Reichinnek and her party also benefited from a backlash to Mr. Merz’s migration measures, and from fears about the rise of the far right. “She had good luck,” said Uwe Jun, a political scientist at the University of Trier.
Her supporters called it something else: the rebirth of a movement. At Die Linke’s election-viewing party in Berlin, the crowd erupted into cheers when early exit polls flashed across the screen. Jan van Aken, a party leader, was greeted onstage with confetti.
“The Left lives,” he said.
Adam Sella contributed from Berlin and Sam Gurwitt from Hanau.