Dov Hikind, a prominent Jewish leader in Brooklyn, endorsed Donald Trump for president in 2020. After Mr. Trump’s recent dinner with two prominent promoters of anti-Semitic rhetoric, Mr. Hikind said he won’t support Mr. Trump again.

“It is over, it is finished,” Mr. Hikind, whose 36-year run as a state lawmaker ended in 2018, said of his support for the former president. “Right now, he’s doing so much damage. He has disqualified himself from any of us supporting him ever again.”

Republicans have tried for decades to boost their generally tepid support among the nation’s Jewish voters, who gave President Biden nearly 70% their vote in 2020 despite Mr. Trump’s argument that they should reward his stalwart backing of the Israeli government. Now, some prominent Jewish leaders say that Mr. Trump has both damaged his nascent 2024 presidential campaign and hampered his party’s outreach as a result of his dinner with the rapper Kanye West and the white nationalist Nick Fuentes, as well as his refusal to apologize for hosting them at his Mar-a-Lago resort.

Former President Donald Trump addressed the Republican Jewish Coalition in Las Vegas by video last month.

Photo: Ronda Churchill/Bloomberg News

Many Jewish leaders, including Mr. Hikind, say a spate of anti-Semitic violence and harassment around the country has created an elevated sense of threat from hateful speech—and that the image of any political leader will suffer for failing to sever ties with Mr. Trump.

While calling out anti-Semitism is a first step, “with a few exceptions, they have failed to do something about it, which in this case would be cutting ties with the people who are having dinner with anti-Semites,” said Andrew Rehfeld, president of Hebrew Union College, the main seminary for the Reform branch of Judaism. “In this case, it requires a distancing, and they are just not doing it.”

House Minority Leader Kevin McCarthy, the party’s likely selection to be the next House speaker, and some others have condemned Messrs. West and Fuentes on their anti-Semitic and racist views while avoiding direct criticism of Mr. Trump.

Some in the GOP have denounced Mr. Trump over the dinner. They include several Republican leaders who might challenge him for the party’s presidential nomination, including former Vice President Mike Pence and Arkansas Gov. Asa Hutchinson, suggesting that the moral and political dangers of Mr. Trump’s actions extend beyond Jewish voters, few of whom participate in Republican primary elections.

House Minority Leader Kevin McCarthy has avoided direct criticism of former President Donald Trump.

Photo: J. Scott Applewhite/Associated Press

“I definitely think that more politicians—more Republicans, too—need to stand up for what’s right,” said Inna Vernikov, a Republican member of the New York City Council who met with Mr. Trump at his invitation earlier this year at Mar-a-Lago. “Even if they support President Trump, when he does something inappropriate, they need to say this is wrong, to condemn it and dissociate yourself from it.”

Benjamin Netanyahu,

who has been designated to return to the office of Israeli prime minister and form a new government, was asked in an NBC interview broadcast Sunday whether Mr. Trump’s actions create a danger for Jews. “If it’s systemic and continues,” said Mr. Netanyahu, one of Mr. Trump’s closest allies among foreign leaders. “And I doubt that it will, because I think he probably understands that it crosses a line.”

David Friedman, who was ambassador to Israel during the Trump administration, and Elan Carr, the State Department’s anti-Semitism envoy under Mr. Trump, both called on the former president to disavow his two guests. Some other Jewish former members of his administration or their representatives didn’t respond to inquiries, among them former Treasury Secretary Steven Mnuchin and the former economic adviser Gary Cohn.

Rep. Lee Zeldin, who some in the GOP are promoting to be party chairman after his loss in this year’s election for governor of New York, this past week called Mr. West a “deranged anti-Semite,” but a spokeswoman said he hasn’t criticized Mr. Trump.

Mr. Hikind, known for his hawkish support of Israel and aggressive advocacy for the large population of Orthodox and Hasidic Jews in his state assembly district, said it was “insane” that a leader of Mr. McCarthy’s stature hadn’t broken with Mr. Trump. “When you start compromising with hate, you become a hater,” he said of the House GOP leader. “Donald Trump is pulling down the Republican party again and again. Disengage, for God’s sake.” 

FBI Director Christopher Wray testified last month that anti-Semitism and related violence are persistent.

Photo: Chip Somodevilla/Getty Images

A spokesman for Mr. McCarthy didn’t respond to a request for comment.

Mr. Trump has said he didn’t know Mr. Fuentes before the dinner meeting, which he said Mr. West had requested to solicit advice. “I had never heard of the man. I had no idea what his views were, and they weren’t expressed at the table in our very quick dinner, or it wouldn’t have been accepted,” Mr. Trump told Fox News this past week. Representatives for Mr. Trump didn’t respond to a request for comment Friday.

Mr. Trump’s Nov. 22 dinner lent prominence to two well-known purveyors of anti-Semitic and racist rhetoric as many Jews feel a heightened sense of personal danger, in part because of the spread of inflammatory language beyond the fringes of the internet. Mr. West, one of the nation’s most famous musicians and fashion designers, has continued his anti-Semitic commentary since the dinner, praising Adolf Hitler during an appearance Thursday. Also that day, he used his Twitter account to post an image of a swastika merged into a Jewish star, which prompted the platform to suspend his account for violating rules against incitement to violence.

The Anti-Defamation League, an anti-hate group focused on protecting Jewish communities, counted 2,717 anti-Semitic incidents in the U.S. last year, up 34% from 2020 and the highest number in its records dating to 1979. Attacks and threats at synagogues, including the Tree of Life shooting in Pittsburgh, which killed 11 people in 2018, and a hostage standoff during Sabbath services this year in Colleyville, Texas, have added to the sense of insecurity. Last month, the Federal Bureau of Investigation issued a broad warning of security threats to New Jersey synagogues and later arrested a man in connection with the matter.

Republican Jewish Coalition leader Norm Coleman says the GOP remains more hospitable to voters, including Jewish voters, than the Democratic Party.

Photo: wade vandervort/Agence France-Presse/Getty Images

In testimony to Congress last month, FBI Director Christopher Wray said that American Jews make up 2.4% of the U.S. population but are the target of about 63% of religious-hate crimes. “Anti-Semitism and violence that comes out of it is a persistent and present fact,” he said.

Both Mr. West, who legally changed his name to Ye, and Mr. Fuentes have used social-media platforms to promote their views. Jonathan Greenblatt, chief executive of the Anti-Defamation League, said extremists have been emboldened by the rise of social media—“which has allowed the kind of poison that was on the margins to move into the mainstream”—and by a lack of pushback from some political leaders.

“In an environment where some political leaders are giving them oxygen and social media has given them an on ramp, extremists have been emboldened, and we have the entrenchment of extremists,” Mr. Greenblatt said. “It’s become part of our culture.”

Jewish voters make up a small share of the electorate, about 3% nationally, and are concentrated in a handful of states. They made up 9% of the voter pool in this year’s midterm elections in New York, 7% in New Jersey and 4% in Florida and California, according to a large survey of the voter pool, known as AP VoteCast.

Surveys have shown that since the mid-1990s, about two-thirds of Jewish voters have aligned with the Democratic Party and about one-quarter with the GOP. Nearly half of Jewish voters in the 2020 presidential election called themselves liberals, VoteCast found, compared with about one-quarter who called themselves conservative.

Mr. Trump won 30% of the Jewish vote, compared with President Biden’s 69% in 2020, the VoteCast survey found, and 33% of Jewish voters backed a Republican House candidate this year. Republican candidates drew higher support in some states, such as Florida, where GOP Gov. Ron DeSantis drew 45% of Jewish voters in his successful re-election campaign. In New York, Mr. Zeldin, who is Jewish, drew 46% of Jewish voters in his unsuccessful campaign for governor.

Some Jewish groups said that the Republican Party was the more welcoming party for Jewish voters, citing what they view as anti-Semitic and anti-Israeli positions on the political left. The challenge that Democrats face in navigating Israel policy was on display in 2019, when the party’s House leaders struggled to respond to Rep. Ilhan Omar (D., Minn.), whose comments about people who “push for allegiance to a foreign country” was viewed as an accusation that Jews who support Israel are disloyal to the U.S. The House passed a broad measure condemning hate in all forms, which Ms. Omar voted for and which critics said insufficiently called out anti-Semitism.

“The reality is, ‘I stand with Israel’ isn’t an applause line at the Democratic-base rallies, but it is at a Republican rally,” said Norm Coleman, the national chairman of the Republican Jewish Coalition and a former Republican senator from Minnesota. 

Mr. Trump has sometimes made statements that appear to suggest that U.S. Jews have a dual loyalty with Israel, saying in 2019, “I think any Jewish people that vote for a Democrat, I think it shows either a total lack of knowledge or great disloyalty.” The Democratic-led House has at times overridden concern by Ms. Omar and other critics of Israel—for example, passing with overwhelming support a resolution in 2019 condemning the global boycott movement against Israel.

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Mr. Coleman said the Mar-a-Lago dinner would have no impact on Jewish support for the Republican Party, which he said was drawing voters of all backgrounds with its policies aimed at taming inflation and crime and securing the border, as well as for its support for Israel. He said he didn’t know what effect the dinner would have on support for Mr. Trump but called it “an inexcusable act.”

As president, Mr. Trump consistently supported Israel’s right-wing government by moving the U.S. Embassy from Tel Aviv to Jerusalem, refraining from criticism of Israel’s settlement-building in the occupied West Bank and ending the nuclear deal with Iran. He also helped normalize relations between Israel and some of its Arab neighbors.

Yaakov Menken, who helps lead an organization of Orthodox rabbis, said the dinner was a minor issue compared with anti-Semitism on the political left. “I don’t think his agreeing to meet with West over dinner overcomes all the things he did in office on behalf of Israel and the Jewish people,” said Rabbi Menken, managing director of the Coalition for Jewish Values. He added that Mr. Trump “definitely remains a friend.”

—Dan Frosch contributed to this article

Write to Aaron Zitner at aaron.zitner@wsj.com