Julian Zelizer is a professor of history and public affairs at Princeton University, and author, with Kevin Kruse, of the new book " Fault Lines: A History of the United States Since 1974. " Follow him on Twitter at @julianzelizer. The opinions expressed in this commentary are his own. View more opinion at CNN.

(CNN) President Donald Trump told the Republican Jewish Coalition in Las Vegas Saturday that Democrats "are advancing by far the most extreme, anti-Semitic agenda in history."

In his ongoing effort to win over a bigger percentage of the American Jewish vote in 2020, the president highlighted his support for Israeli Prime Minister Benjamin Netanyahu and criticized Congresswoman Ilhan Omar in asking American Jews to support the GOP.

The strategy won't work. Traditionally, solid majorities of American Jews have voted for Democratic presidential candidates. The only Republicans who made some progress against this trend were Ronald Reagan, with 39% of the Jewish vote in 1980, and Mitt Romney, with 30% in 2012. Normally, the numbers look more like they did in 2016 -- when Hillary Clinton won 71% of the Jewish vote and Trump got 23%, despite his efforts to use Israel as a wedge issue.

In 2019, the numbers don't look good for Trump. According to Gallup, 71% of Jewish respondents disapprove of the president. In 2018, only 16% of American Jews identified as Republicans. In the 2018 midterms, 79% of American Jewish voters supported Democratic candidates.

Most American Jewish voters remain liberal. They don't support the reactionary agenda that President Trump has championed. For instance, a sizable majority of American Jews hold liberal views about immigration. As a community that has spent much of its history seeking safe harbor and fleeing persecution -- a history that Jews will be talking about in their homes over the upcoming Passover seders -- they are not on board with the President's efforts to build border walls and shut down the asylum seekers.

There is good reason why all of the Jews currently serving in the Senate are Democrats and only two of the Jewish Representatives are Republican.

When it comes to Israel, polls from the American Jewish Committee have shown that most American Jews don't support Prime Minister Netanyahu's positions on the conflict with Palestinians. By large numbers, American Jews continue to support a two-state solution, they want to curtail settlements, and they believe in the peace process. The American Jewish Committee found that only 34% of American Jews support how Trump is handling American-Israeli relations. The notion that being "pro-Israel" means endorsing the Netanyahu government is a myth propagated by the right, one which most American Jewish voters don't agree with.

To be sure, President Trump's hardline rhetoric about the current government of Israel does play with some minority parts of the American Jewish community. The President has also been exploiting concerns that exist over the rhetoric used by Congresswoman Omar and other progressives in their criticism of AIPAC, such as her tweeting out "All About the Benjamins" and making statements that, some believed, implied Jews have a dual loyalty to the United States and Israel. Although Omar apologized for this and other issues, Democrats have not been able to quell the concerns about renewed anti-Semitism on the left. But as the President finds some sympathetic audiences with his cynical deployment of the issue, he has not been able to grow support within the GOP.

Then there is President Trump himself. There is now a long and well-documented record of his willingness to use anti-Semitic tropes and images, even as he claims to be the best President for American Jews.

He has retweeted out anti-Semitic imagery on several occasions, while he has consistently refused to come down hard on white nationalist forces within the United States who are the champions of the most lethal forms of anti-Jewish sentiment. The infamous neo-Nazis at Charlottesville chanted "The Jews Will Not Replace Us!" He has joked about Jews enjoying bargaining and money.

Even in the speech to the Jewish Republicans, he employed the dual loyalty rhetoric that Republicans have been deriding with Congresswoman Omar when he spoke about "your Prime Minister." Indeed, the entire notion that American Jewish voters can be won over simply through hardline positions about Israel plays directly into the worst stereotypes about the community. The hypocritical way in which he manipulates this issue is an insult to voters.

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Despite his predictions, President Trump is actually one of the worst things to happen to Republicans who have been working to increase their hold on the American Jewish electorate. Putting aside his own bluster, he has done a great deal to isolate, marginalize and even scare American Jewish voters who might have been giving some thought to switching their historic allegiance from the party of Franklin Roosevelt.

If they think that large numbers are going to be bolting to the party of Trump, they should take a harder look at the President's actual record.