Zohran Mamdani’s insurgent campaign for New York City mayor is casting a spotlight on a rising faction within the Democratic Party and beyond that rejects unconditional support for the Israeli government and is more sympathetic to the plight of Palestinians.

Mr. Mamdani’s outspoken condemnation of the “genocide” in the Gaza Strip, along with his pledge to honor the International Criminal Court’s arrest warrant for Israeli Prime Minister Benjamin Netanyahu, has sparked fierce backlash from pro-Israel advocates.

It also has energized voters who feel no personal ties to Israel, who denounce the scale of the military response in Gaza to wipe out Hamas after the Oct. 7, 2023, terrorist attacks in Israel, and who are increasingly frustrated by taxpayer dollars being funneled abroad while urgent domestic needs go unmet.

Dov Waxman, a political science professor at the University of California, Los Angeles, who specializes in U.S.-Israeli relations and Jewish politics, said Mr. Mamdani’s front-runner status and nearly 13-percentage-point win in the Democratic primary would have been “inconceivable” not long ago, given New York’s sizable Jewish population and the bipartisan pro-Israel consensus.

“The fact that Mamdani won the Democratic primary election and looks likely to win the general election testifies to the profound change that has taken place over the past decade or so among Democratic voters, including Jewish voters, vis-a-vis the Israel-Palestine issue,” Mr. Waxman said.

Across the country, Democrats are rejecting donations from the American Israel Public Affairs Committee, also known as AIPAC, an influential pro-Israel lobbying group, as they seek to energize grassroots activists.

Graham Platner in Maine, Mallory McMorrow in Michigan and James Talarico in Texas are among the Democratic candidates for U.S. Senate who have sworn off AIPAC dollars.

“Our taxpayer dollars can build schools and hospitals in America, not bombs to destroy them in Gaza,” Mr. Platner told a crowd in Portland, Maine, earlier this year, sparking a standing ovation.

The stance creates daylight between them and party elders such as Senate Majority Leader Charles E. Schumer, the highest-ranking Jewish leader in American government and a longtime advocate for Israel. He has received nearly $2 million in contributions from AIPAC over the years, according to OpenSecrets.org.

It also puts the candidates closer to far-left figures such as Sen. Bernard Sanders, Rep. Alexandria Ocasio-Cortez and the rest of Congress’ “Squad,” who have not received a dime of AIPAC money and who have been vocal in their criticism of Israel and support for Palestinians.

Only 11 of the 33 first-term House Democrats joined a recent AIPAC-sponsored trip to Israel, a notable decline from past years, The New York Times reported.

Asked about the changing political tides, AIPAC spokesperson Marshall Wittman cited Election Day results as a cautionary tale, suggesting Democrats may want to think twice before following in Mr. Mamdani’s footsteps.

“Ninety-five percent of AIPAC-endorsed Democrats won their election last fall, demonstrating that being pro-Israel is good policy and good politics,” Mr. Wittman said in an email. “Through AIPAC’s PAC, our members raise more money for Democratic candidates than any other political action committee in the country.”

Still, U.S. policy toward Israel is emerging as an early litmus test for potential 2028 presidential contenders.

Former Transportation Secretary Pete Buttigieg — widely seen as a breakout figure from the 2020 primary and one of the Democratic Party’s most effective communicators — was on the defensive after offering a mealy-mouthed response when asked whether he would oppose sending weapons to Israel.

Meanwhile, the Democratic National Committee struggled to reach a consensus. It postponed a vote at its summer meeting on two resolutions concerning the U.S.-Israel relationship, one of which proposed a military arms embargo and the suspension of American military aid to Israel.

Mr. Mamdani is serving as the most significant test case, and he acknowledges he cannot halt the unfolding events if elected mayor.

Still, he said he feels the need to state his “commitment to humanity to safety to justice for all people — that extends to everyone, Israelis, Palestinians and everyone else.”

“Of course, I condemn Hamas. Of course, I have called Oct. 7 what it was, which was a horrific war crime, and, of course, my belief in a universality in international law is also the same set of beliefs that led me to describe what’s happening in Gaza as a genocide,” Mr. Mamdani said recently on ABC’s “The View.” “What we see is a war crime being answered with war crimes.”

His words reflect a broader reckoning within the Democratic Party that has picked up speed during the war in Gaza.

Polls show Democrats, both young and old, have become more sympathetic to the Palestinians and much more critical of Israel.

Democratic voters are increasingly receptive to limiting or suspending military aid to Israel, voicing support for Palestinian statehood and openly criticizing Mr. Netanyahu’s leadership.

“Mamdani’s views, therefore, are more mainstream among Democrats than they once were,” Mr. Waxman said. “Mamdani’s views reflect those of progressive Democrats, and if present trends continue, they could well become the position of the Democratic Party in the future.”

Nina Turner, co-chair of Mr. Sanders’ 2020 presidential campaign, said the Democratic Party’s move away from unconditional support for Israel is being driven from the grassroots, not imposed from the top down.

“The vast majority of Democrats, but also Americans in general, are looking at the war in Gaza through different eyes than when they did when it first started,” she said. “So the tide certainly is turning, and it’s turning among the average everyday American people.”

Ms. Turner learned firsthand the political cost of challenging pro-Israel forces when she lost to Shontel Brown in the 2021 special election and the 2022 rematch for Ohio’s 11th Congressional District.

Despite those setbacks, Ms. Turner insists that resistance to blind support for Israel is gaining ground.

She cited the “uncommitted movement” in the 2024 Michigan Democratic primary. This protest vote drew tens of thousands of ballots from voters dissatisfied with the Biden administration’s stance on Israel and Gaza.

The group later staged a sit-in at the Democratic National Convention to protest the party’s refusal to grant stage time to a pro-Palestinian voice. It later declined to endorse Vice President Kamala Harris after she assumed the top spot on the ticket.

Ms. Turner predicted a continued shift within the Democratic Party. She said a time will come when grassroots activists view AIPAC endorsements with the same skepticism they reserve for dark money from other outside groups.

“You know how it’s almost like having a scarlet letter if you’re a Democrat and you got money from or an endorsement from, let’s say, the NRA, the National Rifle Association, right?” she said. “I think there is going to come a time because of the grassroots push that that will be the same for AIPAC.”

Still, it is not an entirely partisan endeavor.

Prominent figures within the MAGA movement have also called for reassessing U.S. policy toward Israel, most notably Rep. Marjorie Taylor Greene of Georgia.

Ms. Greene, a top Trump ally in Congress, claims to be under attack from AIPAC after questioning continued military aid and criticizing specific actions of the Israeli government.

Like Mr. Mamdani, Ms. Greene condemned the 2023 Hamas attack and has called for the release of all hostages.

She also expresses deep concern over what she describes as “the genocide, humanitarian crisis and starvation happening in Gaza.”

“I think we are in a whole different time. I think Americans have very much become aware that Israel is a foreign government that has been meddling, not only in campaigns and elections, but also meddling in government policy … as well as dictating what America does in foreign wars,” Ms. Greene said on OAN. “That has become a major problem for many Americans, especially young Americans.”

That generational divide spilled into public view when former House Majority Leader Steny H. Hoyer, Maryland Democrat, faced backlash over remarks he made in a video recorded during an AIPAC-sponsored trip to Israel.

“Contrary to world opinion, Israel has been doing everything it possibly can to ensure that there is minimal damage to civilians who are not part of Hamas’ army,” Mr. Hoyer said in the video. “Unfortunately, the world is not seeing that.”

Rep. Ro Khanna, California Democrat and another possible 2028 contender, said Mr. Hoyer’s remarks “are why our base thinks Democratic leaders are out of touch.”

“It’s hard b/c I like you. But the old guard is why our numbers are in the tank!” Mr. Khanna said on X. “It’s time to be bold & speak this blunt truth & for a new generation to lead a rebirth of our party.”

AIPAC defended Mr. Hoyer: “@RoKhanna is mad his colleague got the facts first-hand.”

Mr. Khanna shot back, “@RepStenyHoyer did you really call @AIPAC to defend you? And you wonder why the majority of Democrats are fed up with our leaders & are done with the status quo. Step aside, make way for new leaders.”

The generational divide is also in New York, where 67-year-old former Gov. Andrew Cuomo is positioning himself as a counterweight to the 33-year-old Mr. Mamdani.

Mr. Cuomo is touting endorsements from prominent Jewish organizations and criticizing Mr. Mamdani for what he claims was a delayed response to the controversial “Globalize the Intifada” slogan. Mr. Cuomo’s strategy is clear: to appeal to voters unsettled by Mr. Mamdani’s rhetoric and recast himself as a stabilizing force in a rapidly evolving political landscape.

“@ZohranKMamdani continues to play word games instead of showing moral clarity,” Mr. Cuomo said Sunday on X. “Today I again call on him — directly and unequivocally — to denounce this phrase and to reject any movement that glorifies violence or targets Jewish people.”

Meanwhile, Mr. Mamdani shared a photograph of himself over the weekend standing with Palestinian New Yorkers with whom he met to discuss “what they and their families have endured as the genocide in Gaza continues, funded by our government.”

“In the face of immeasurable grief, they have showed unbreakable resilience,” Mr. Mamdani said.

• Seth McLaughlin can be reached at smclaughlin@washingtontimes.com.