Rise of the Mamdani Clones

After the 2024 humiliation, the left is back. It could hurt the party in 2026.

What could get in the way of a coming 2026 Democratic wave, given history and the current public mood? Nothing but the Democratic Party itself, which is sitting placidly by as the progressives who lost them last year’s election mobilize to take over even more of the party. Bernie Sanders may never be president, but he’s a kingmaker.

The left’s top focus is on purifying current Democratic seats, replacing less-extreme incumbents with Mamdani-like democratic socialists.

At least 20 Democratic representatives and four senators are on the casualty list, retiring to make their seats available to progressive challengers rather than be beaten by them. The left, fueled by Mayor-elect Zohran Mamdani’s New York City victory, are moving against those who remain, challenging dozens of incumbents from New York to California. The national party organizations have lost control, as progressive super PACs pour money into the fight, guided by Mr. Sanders, who is endorsing widely and early and stockpiling his own cash for his chosen candidates.

The left’s top focus is on purifying current Democratic seats, replacing less-extreme incumbents with Mamdani-like democratic socialists. A case in point: Brad Lander, the New York City comptroller, raised his profile during his run in the recent mayoral race by getting arrested by Immigration and Customs Enforcement. He didn’t win, but did forge a ranked-choice voting alliance with Mr. Mamdani and earned Mr. Sanders’s approval.

With endorsements from Messrs. Mamdani and Sanders in his pocket, Mr. Lander this week announced his plan to challenge Rep. Dan Goldman, on grounds the incumbent is a political wimp. This is the same Dan Goldman who, as former then-Rep. Adam Schiff’s right-hand man, served as lead counsel in the first impeachment of Donald Trump. He supports Medicare for All and the Green New Deal, is among the loudest voices for millionaire taxes, and has a near-perfect progressive voting record. His sins? Being born wealthy and supporting Israel. Mr. Lander describes Mr. Goldman as a member of an “oligarchy” who does pro-Israel groups’ “bidding.”

Mr. Goldman is hardly alone, even in his own state. Rep. Adriano Espaillat has drawn a primary challenge from Darializa Avila Chevalier, a community organizer who is backed by Justice Democrats, the group who propelled Rep. Alexandria Ocasio-Cortez to office. Mr. Espaillat—the highly progressive chairman of the Congressional Hispanic Caucus—stands accused of taking corporate PAC money. Progressives are also challenging New York Democrats Ritchie Torres, Gregory Meeks, Grace Meng and Laura Gillen. Even House Minority Leader Hakeem Jeffries faced a threat from New York City Councilman Chi Ossé, a Democratic socialist, until Mr. Ossé dropped his bid last week.

But the left’s zeal is also propelling candidates into open and battleground races—no matter the general-election risks. Maine Rep. Jared Golden clung to his rural Maine district by less than 1 point as Mr. Trump won it by 10 last year, and only via a pragmatic voting record. The primary to replace him features two avowed progressives, racing to the left. And progressives are stacking up cash and endorsements in primaries to take on the most vulnerable Republicans in battleground states from Pennsylvania to Arizona and Wisconsin. In the contest to challenge vulnerable Republican California Rep. David Valadao, school-board activist Randy Villegas is using a Sanders endorsement and dollars to outpower moderate state Rep. Jasmeet Bains.

The risks of the Sanders takeover were further highlighted in Texas this week, when former Rep. Colin Allred was pressured out of a Senate run, to clear the decks for uber-progressive Rep. Jasmine Crockett. Mr. Allred, a former NFL linebacker, lost to Sen. Ted Cruz last year by 8 points, significantly outperforming Kamala Harris. Democrats have their best shot at a statewide office in Texas in years, given the general electoral climate and a bloody GOP primary between Sen. John Cornyn and state Attorney General Ken Paxton. Ms. Crockett still must beat state House member James Talarico, but backing for her is pouring in and Democrats face the real prospect that their “best” shot will be in the hands of a freshman Democrat who has clawed her way to notoriety through creative slanging matches.

Lost in all this maneuvering was the release of a recent report from a center-left group, Welcome, which Semafor reports “consulted hundreds of thousands of voters over six months for its broad findings, including that 70% of voters think the Democratic Party is ‘out of touch’ ” on issues ranging from transgenderism to climate—everything the reascendant progressive left stands for.

The report’s findings reflect what much of the Democratic Party was thinking in the wake of last year’s election thumping. But that looks to be gone already, talk of “abundance” or new “third way” politics buried beneath Mr. Mamdani’s victory—no matter how little New York City reflects America. Republicans face a difficult coming midterm, no doubt. But if progressives emerge from this primary season firmly back on top the party, they might just mitigate some of that GOP risk.

Write to kim@wsj.com.