Sen. Bernie Sanders (I-VT) and Rep. Alexandria Ocasio-Cortez (D-NY) at a stop on their Fighting Oligarchy tour on April 12 in Los Angeles, California. | Mario Tama/Getty ImagesThe signs have been bubbling up for months: The Democratic base is fed up with the status quo of their party. Democratic voters believe their party leaders are out of touch, and they don’t think they’re rising to meet this moment. They want more confrontation with President Donald Trump, and they’re hungry for an inspiring, forward-looking economic vision. That sentiment comes through in just about all the polling of the party, in focus groups with voters, and in anti-Trump protests and populist rallies since Trump’s inauguration.The latest sign of this frustration might just be the stunning result of New York City’s mayoral primary this week. The victory of a self-proclaimed Democratic Socialist Zohran Mamdani over the embodiment of the Democratic establishment, former New York Gov. Andrew Cuomo, all with high turnout and a comfortable margin of victory, suggests Democratic voters are open to radical change. Of course, there are plenty of peculiarities that make a New York City primary contest a bit of a unique case: a toxic early front-runner, ranked-choice voting, and an open field of candidates during an off-year election. These specifics all make it risky to try to draw national implications from a local race.But there’s at least one big warning for national Democrats from this upset: the kind of anti-establishment energy that boosted Mamdani exists in Democratic enclaves around the country. It feels familiar — reminiscent of 2009 and the rise of the Tea Party among the Republican Party’s conservative base that ended up remaking the GOP. The energy also feels similar, but more widespread, than what boosted progressive victories during primaries in Trump’s first term. And that energy suggests that the forces that remade the GOP could be aligning for Democrats to face a Tea Party moment of their own. It remains to be seen whether this revolt will turn into a leftward shift of the party’s ideological positions. But it appears at least likely to result in targeting older and established incumbents, replacing the party’s leadership, or, at a minimum, forcing those leaders to be more aggressive against Trump, accommodating of younger leaders, and less complacent when faced with populist anger. So as the national Democratic Party continues its post-2024 soul-searching, its incumbents and leaders are getting a clear warning. The ingredients are here for a populist revolt within the Democratic Party. Will leaders adjust and listen?Democratic voters are on board with generational changeThis year’s Democratic rage is very different from the last time Trump was elected president: The base wants not just confrontation with Republicans but to replace the party’s leadership entirely.Consider a June Ipsos poll of Democrats, the latest of many surveys showing the Democratic base is unhappy with the state of their party. About half of Democrats are “unsatisfied with current leadership,” and 62 percent said “party leaders should be replaced.” This dissatisfaction is historic. Going back to 2009, Democrats haven’t been this upset with their party before. As noted, the last time a party’s base was worked up was during the Republicans’ Tea Party movement, which culminated in Trump’s GOP takeover.Unlike previous moments of Democratic infighting, this divide isn’t primarily about ideology. That same June poll found that Democrats want their party to focus more on affordability, on getting the wealthy to pay more on taxes, and health care expansion. Older and younger Democrats are broadly in agreement about prioritizing economic concerns over social issues — and there aren’t that many differences between what younger and older Democrats want to prioritize.Instead, it’s a fight over priorities. There’s a huge gulf between what each cohort of Democratic voters think their party does focus on and what it should focus on, particularly because younger Democrats are more progressive and think their leaders don’t care enough about universal health care, affordability, or taxing the rich.On this front, age is becoming the big dividing line within the party. Previous polls have shown that overwhelming shares of Democratic voters want their party to run “younger candidates that represent a new generation of leadership” and “encourage elderly leaders to retire and pass the torch to the younger generation.” Dissatisfaction with “the establishment” is overwhelming. The result of these combined feelings may lead to more Mamdani moments, according to some activists and strategists. Already a handful of younger candidates have announced primaries of longtime incumbents in California, Illinois, and Indiana. More are expected in blue states like Massachusetts and New York, including in the New York City region. Even party activists have announced that primarying older incumbents should be a party priority.And there are signs this energy exists at every level of politics. At the grassroots, liberal, anti-Trump energy is still bubbling up through smaller but more frequent protests. Though it may seem like the 2017–18 #Resistance protests were more visible than those of 2025, various tracking efforts show that protests this year are happening more often and in a more localized manner. One metric from Harvard, for example, finds that there have been more than 15,000 protests since Trump’s second inauguration. In that same time in 2017, the number was smaller: over 5,000 protests.How far can we expect this new movement to go?As far as turning this energy into political action, there are also clear signs. Since Tuesday’s primary, the progressive political organization Run for Something, which recruits and supports young people who want to run for office, is reporting a surge in candidate recruitment, with more than 2,700 people signing up to explore campaigns as of Friday afternoon.The organization’s president, Amanda Litman, says it’s one of the biggest spikes in interest since Trump’s election, mirroring the grassroots intensity generated after the Elon Musk-backed Department of Government Efficiency began to make cuts across the federal government and when Democrats helped avoid a government shutdown this spring. And it brings the number of young potential candidates who have expressed interest in running for office since Trump’s election to more than 50,000 people.“We are seeing more young people than ever before raise their hands to run, not in spite of the chaos, but because of it. They are bringing urgency, boldness, energy, and their lived experience to the table. They are ready to change what leadership looks like in this country,” Litman said.How successful these efforts at generational change will be remains to be seen.The GOP’s internal revolt back in 2009 and 2010 contributed to the party’s takeover of the House by boosting conservative and Republican enthusiasm, but Tea Party candidates had more success in winning primaries than winning general elections. (That dynamic shifted some after Trump’s total takeover of the party.)Similarly, calls for the Democrats to move left, and embrace a more progressive agenda, seem to resonate with a party whose membership has become much more liberal over the last 20 years. But that might be a misreading of a national electorate’s mood, particularly after a presidential election that showed large segments of the electorate were hostile to Democrats’ “liberal” identity.Insurgent populist candidates have many steps ahead to win primaries and then prove they can win general elections. But it’s not inconceivable to think they can do it. There was a time when the GOP’s populist wing was considered fringe — extreme, even. We all know how that turned out.