American Jews 'disloyal' to their own people and Israel if they vote Democratic: Trump Polls show the vast majority of American Jews have voted for Democrats.

President Donald Trump doubled down Wednesday on his controversial assertion that Jewish Americans who vote for a Democrat are "very, very disloyal to Israel and the Jewish people," continuing his effort to make support for Israel a political wedge issue ahead of the 2020 election.

The day before, while attacking Democratic Rep. Rashida Tlaib and other Democratic congresswomen of color who had been critical of Israel's policies, Trump told reporters that he thought "any Jewish people that vote for a Democrat, I think it shows either a total lack of knowledge or great disloyalty."

Asked on Wednesday to clarify to whom they were being disloyal -- as critics called his comments anti-Semitic -- the president said he was referring to Israel and the Jewish people in general.

“In my opinion, if you vote for a Democrat, you're being very disloyal to Israel and you're being very disloyal to Jewish people," Trump told reporters before departing the White House en route to Kentucky.

Historically, Jews have overwhelmingly voted for Democratic candidates.

Seventy-nine percent of Jewish voters cast a ballot for a Democrat in the midterms last year, according to exit poll data. In the 2016 presidential election, 72% of Jews voted for Trump's Democratic rival, Hillary Clinton.

An analysis of ABC News data in 2018 found that 41% of Jews identified themselves as liberals, more than any other religious group.

"Let’s be clear: What @POTUS said was #antiSemitic," the CEO of the Anti-Defamation League, Jonathan Greenblatt, wrote on Twitter, about Trump's initial remark. "The charge of disloyalty or dual loyalty has been used against Jews for centuries. Almost a year after the #Pittsburgh shooting, as #antiSemitism continues to rise, it’s bewildering that we still need to have this conversation."

Asked Wednesday by a reporter if his comments about “disloyalty” were anti-Semitic, Trump replied that they were not.

"It's only anti-Semitic in your head," he told the reporter.

Democratic lawmakers lashed out against the president.

"When President Trump uses a trope that has been used against the Jewish people for centuries with dire consequences, he is encouraging—wittingly or unwittingly—anti-Semites throughout the country and the world," Senate Minority Leader Chuck Schumer, D-N.Y., said in a statement Wednesday. "Enough."

Democratic 2020 candidates blasted his initial comments as offensive and anti-Semitic. Former Vice President Joe Biden said Trump's remark was "inexcusable" and "beneath the office" of the president, while Sen. Cory Booker, D-N.J., contrasted Jewish teachings about love and kindness with what he called Trump's efforts "to try to divide us against each other, to demean and degrade us."

"I am a proud Jewish person and I have no concerns about voting Democratic," Sen. Bernie Sanders, D-Vt., tweeted. "And in fact, I intend to vote for a Jewish man to become the next president of the United States."

ABC News' Gary Langer and Adam Kelsey contributed reporting to this article.