A slew of influential ultra-Orthodox Jewish leaders endorsed Mr. Yang, motivated by one overriding issue: “Yeshivas, yeshivas, yeshivas.”The campaign material began appearing in Yiddish earlier than usual this year, declaring that the best defense that ultra-Orthodox Jews in New York City could have against a hostile world would be to elect Andrew Yang as mayor.One ad, invoking a passage from the Babylonian Talmud, told voters that Mr. Yang was the sort of honest man who is loved by God, not someone “who says one thing with his mouth but means another in his heart.”Another ad cast the choice in existential terms, urging people to vote for Mr. Yang because he alone supports “our right to educate our children according to our fundamentals” and “values our way of life.”With the June 22 Democratic mayoral primary roughly a month away, Mr. Yang, a former 2020 presidential candidate, has been able to push to the top of the contest through a potent mix of celebrity, optimism and tireless outreach, both in person and on social media.As he did in his presidential candidacy, which had support from a broad spectrum of disaffected voters, Mr. Yang has been able to widen his appeal in New York, attracting a significant following from influential ultra-Orthodox Jewish leaders.There are at least 500,000 Orthodox Jews in the New York area, by some estimates, and the endorsement of ultra-Orthodox leaders is highly coveted because the community is seen as a formidable voting bloc, especially in a race that has so far not energized the electorate.The endorsement of ultra-Orthodox leaders is highly coveted because the community is seen as a formidable voting bloc.James Estrin/The New York TimesThe key for Mr. Yang was his early declaration that he intended to take a laissez-faire attitude toward Hasidic yeshivas, the private schools to which almost all ultra-Orthodox families send their sons, as well as toward the schools where they educate their daughters.The yeshiva system has faced intense criticism over the failure of some schools to provide a basic secular education. Some also operated secretly during the pandemic, in violation of public health rules.“We shouldn’t interfere with their religious and parental choice as long as the outcomes are good,” he told The Forward, a Jewish publication, in February.That approach has helped him undercut rivals, particularly the Brooklyn borough president, Eric Adams, a former state senator who has a long working relationship with the Orthodox community.In the 2013 Democratic mayoral primary, Hasidic groups in Borough Park, Brooklyn, backed Bill de Blasio, who had once represented the area in the City Council.But in the last two presidential elections, neighborhoods with large ultra-Orthodox populations were islands of deep red in overwhelmingly blue Brooklyn. Some precincts in Borough Park voted for President Donald J. Trump by more than 90 percent in 2020.It remains to be seen how much influence Hasidic leaders will have in the Democratic primary; most ultra-Orthodox Jews support the Republican Party, according to a study published last week by the Pew Research Center, and the 2020 presidential election results in Orthodox Brooklyn seem to bear that out.Nonetheless, for Hasidic leaders, the decision to endorse a newcomer like Mr. Yang over a known quantity like Mr. Adams highlights their anxiety after a yearslong series of calamitous events: a devastating pandemic, a rise in anti-Semitic hate crimes and a long history of clashes with secular authorities over issues like social distancing, measles outbreaks and high school curriculums.Mr. Yang comes to city politics without the baggage of those past clashes. Capitalizing on that blank slate, he has won over allies with well-honed rhetoric on religious freedom, a sophisticated messaging campaign in Yiddish media and a willingness to adopt the hands-off approach favored by Hasidic leaders.“The most burning issue is yeshivas,” said Alexander Rapaport, a community leader who has organized voter registration drives in Borough Park in the run-up to the primary. “It’s not like something else is issue No. 2. Everything else is issue No. 25. The first 24 issues are yeshivas, yeshivas, yeshivas.”Alexander Rapaport, a community leader in Borough Park, said that for many voters, where candidates stood on yeshivas was a defining issue. Kevin Hagen for The New York TimesIn past elections, debates over yeshivas often centered on the allocation of public funds to the religious schools, which receive millions of federal, state and city dollars through education and child care programs.But the political conversation changed after a 2015 legal complaint filed by yeshiva graduates who said they had been given little secular education. That complaint led the city to open an inquiry that found that 26 of 28 yeshivas that were investigated were not meeting a legal requirement to provide education “substantially equivalent” to that provided in city public schools.No action was taken, but it prompted a citywide dialogue that cut to the heart of the yeshiva’s role in Hasidic society and profoundly insulted many in the community. There are more than 50,000 students in Hasidic schools in New York City, according to a 2017 report by Young Advocates for Fair Education, an ultra-Orthodox advocacy group.“The perceived threat to the autonomy of the yeshivas is greater now than it ever has been in part because there are critics from within the community publicizing what they see as the problems with the yeshiva system in a way that hasn’t happened before,” said Nathaniel Deutsch, a professor at University of California, Santa Cruz.Mr. Yang’s approach to the community was on full display at a recent event in Midwood, Brooklyn, where he received the endorsement of two local politicians, Assemblyman Simcha Eichenstein and Councilman Kalman Yeger.Standing before a crowd of reporters, Mr. Yang vowed to fight anti-Semitism and told Hasidic voters they were part of the “beautiful mosaic” of New York City.But when asked by The New York Times about yeshivas, Mr. Yang stood quietly behind Mr. Eichenstein and Mr. Yeger as they heatedly defended the schools, attacked “so-called advocates” for reform and decried the city investigation.Mr. Yang appeared bewildered by their anger — at one point, Mr. Yeger accused members of the City Council of being “OK with our kids getting blown up” — and sought to calm tensions with a joke about the “high-value add” they made to his campaign.He then took the microphone and criticized the city for allowing investigators “to check for infractions of various kinds” in yeshivas. He said he would take a different approach as mayor..css-1xzcza9{list-style-type:disc;padding-inline-start:1em;}.css-3btd0c{font-family:nyt-franklin,helvetica,arial,sans-serif;font-size:1rem;line-height:1.375rem;color:#333;margin-bottom:0.78125rem;}@media (min-width:740px){.css-3btd0c{font-size:1.0625rem;line-height:1.5rem;margin-bottom:0.9375rem;}}.css-3btd0c strong{font-weight:600;}.css-3btd0c em{font-style:italic;}.css-w739ur{margin:0 auto 5px;font-family:nyt-franklin,helvetica,arial,sans-serif;font-weight:700;font-size:1.125rem;line-height:1.3125rem;color:#121212;}#NYT_BELOW_MAIN_CONTENT_REGION .css-w739ur{font-family:nyt-cheltenham,georgia,’times new roman’,times,serif;font-weight:700;font-size:1.375rem;line-height:1.625rem;}@media (min-width:740px){#NYT_BELOW_MAIN_CONTENT_REGION .css-w739ur{font-size:1.6875rem;line-height:1.875rem;}}@media (min-width:740px){.css-w739ur{font-size:1.25rem;line-height:1.4375rem;}}.css-9s9ecg{margin-bottom:15px;}.css-1jiwgt1{display:-webkit-box;display:-webkit-flex;display:-ms-flexbox;display:flex;-webkit-box-pack:justify;-webkit-justify-content:space-between;-ms-flex-pack:justify;justify-content:space-between;margin-bottom:1.25rem;}.css-8o2i8v{display:-webkit-box;display:-webkit-flex;display:-ms-flexbox;display:flex;-webkit-flex-direction:column;-ms-flex-direction:column;flex-direction:column;-webkit-align-self:flex-end;-ms-flex-item-align:end;align-self:flex-end;}.css-8o2i8v p{margin-bottom:0;}.css-12vbvwq{background-color:white;border:1px solid #e2e2e2;width:calc(100% – 40px);max-width:600px;margin:1.5rem auto 1.9rem;padding:15px;box-sizing:border-box;}@media (min-width:740px){.css-12vbvwq{padding:20px;width:100%;}}.css-12vbvwq:focus{outline:1px solid #e2e2e2;}#NYT_BELOW_MAIN_CONTENT_REGION .css-12vbvwq{border:none;padding:10px 0 0;border-top:2px solid #121212;}.css-12vbvwq[data-truncated] .css-rdoyk0{-webkit-transform:rotate(0deg);-ms-transform:rotate(0deg);transform:rotate(0deg);}.css-12vbvwq[data-truncated] .css-eb027h{max-height:300px;overflow:hidden;-webkit-transition:none;transition:none;}.css-12vbvwq[data-truncated] .css-5gimkt:after{content:’See more’;}.css-12vbvwq[data-truncated] .css-6mllg9{opacity:1;}.css-1rh1sk1{margin:0 auto;overflow:hidden;}.css-1rh1sk1 strong{font-weight:700;}.css-1rh1sk1 em{font-style:italic;}.css-1rh1sk1 a{color:#326891;-webkit-text-decoration:underline;text-decoration:underline;text-underline-offset:1px;-webkit-text-decoration-thickness:1px;text-decoration-thickness:1px;-webkit-text-decoration-color:#ccd9e3;text-decoration-color:#ccd9e3;}.css-1rh1sk1 a:visited{color:#333;-webkit-text-decoration-color:#ccc;text-decoration-color:#ccc;}.css-1rh1sk1 a:hover{-webkit-text-decoration:none;text-decoration:none;}“To the extent that there are issues in individual schools, I think we have to come together with the community and say ‘Look, like, is there something we can do to help?’” Mr. Yang said.“When there are issues, the approach should be one of correction and collegiality rather than contentiousness and adversarialness,” he added. “Which, unfortunately I think, has been the dynamic that the city has engendered for far too long.”Mr. Yang has expressed a willingness to adopt a hands-off approach to yeshivas, winning over many Hasidic leaders.Dave Sanders for The New York TimesMr. Adams has also praised yeshivas, saying he was “genuinely impressed” by one of the schools investigated by the city when he visited in March. But he has stressed that they must meet city standards and seemed to favor intervention when they do not.“We have to ensure that these yeshivas — those that are failing, which is not all the yeshivas, but those that are failing — we have to ensure that they meet the minimum standards,” he recently told The New York Times.The endorsements for Mr. Yang have been notable for how early they arrived. Hasidic leaders tend to wait until polls have established a favorite so they can try to back the winner, said David M. Pollock, the public policy director of the Jewish Community Relations Council of New York.But the fact that ultra-Orthodox voters have voted as a bloc in the past does not mean they are a monolith, Mr. Pollock said.That has been especially clear at the local level. Even in 2013, when Mr. de Blasio won the Borough Park neighborhood, he did so only by a slight margin over William C. Thompson Jr., who beat him in other neighborhoods with large ultra-Orthodox populations.“The dynamic is not that there is one bloc vote, but that there are multiple political players who can deliver votes wholesale,” Mr. Pollock said. That can be especially potent in an election with ranked-choice voting, which this mayoral race is using for the first time.“If you’re not going to endorse someone as your No. 1, you can say, ‘You’ll be our No. 2,’” Mr. Pollock said. “That’s not bad if you can sway 6,000 votes.”Mr. Yang has sought to appeal to Hasidic voters on issues besides education, including support for the right of parents to choose a circumcision ritual, metzitzah b’peh, which is used by a minority of Hasidic mohels and has transmitted herpes to babies, and support for Israel in its conflict with Hamas.But yeshivas have become the dominant issue in part because they play a larger role in Hasidic society than schools do in the secular world, Professor Deutsch said.They employ many Hasidic people, act as a social network that connects people with jobs and marriage prospects and are a primary medium through which the community’s history, values and Yiddish language are passed on to new generations, he said.They are also an important lever of power for community leaders, who can threaten to bar a child from yeshiva to enforce standards of behavior on their parents, such as a prohibition on renting property to gentrifiers, Dr. Deutch said.Indeed, Yoel Greenfeld, a young man leaving prayers at a 24-hour synagogue in Borough Park, said he would vote for Mr. Yang in the general election because Hasidic leaders endorsed him. But he cannot vote in the primary because he is a registered Republican.“I’ll vote for Yang because the community here wants Yang, and when people say that they mean the leaders want Yang,” Mr. Greenfeld said. “My opinion is nothing compared to theirs. But personally, I want a Republican.” More