Like many of his controversial comments in the past, Donald Trump stepped on his toes by hesitating to say that he would accept the outcome of the November 8th election, former vice presidential candidate Joseph Lieberman said on Thursday.

“I thought Trump, actually for part of it, did better than before. He seemed a little more disciplined. But then he made a big mistake,” Lieberman told Jewish Insider in a phone interview on Thursday. “This is really a violation of the kind of broadly non-partisan American ethic that in the end, you accept the results of the election and that you allow a peaceful transfer of power. I think that will worry people. It probably won’t upset too many of his supporters, but I think for people who have thought at some point about supporting Trump and have gone increasingly concerned in recent days about his focus on the election being rigged – which there’s no evidence of that, whatsoever – what he said last night, persuaded the persuadable that Hillary Clinton is their best choice.”

Lieberman faced a similar choice when he ran for vice president on the Democratic ticket with former Vice President Al Gore in 2000. After the U.S. Supreme Court stopped a recount of uncounted ballots in the state of Florida, Gore eventually conceded the race to George W. Bush despite having reservations about the outcome being determined by justices and having won the popular vote. “The U.S. Supreme Court decision left open a door to another step for Gore, which was to go back to the Florida Supreme Court and ask fro a recount of all the votes,” Lieberman recalled the day he called a ‘frustrating’ moment for the ticket. “Vice President Gore, to his credit, late on the night that the Supreme Court decision came down, he said, ‘It’s time for the good of the country to end this.’ Gore, really in the spirit of this nonpartisan ethic, said, ‘We fought hard, we fell the result is unfair, but now we better accept it and let the country move on.’ That was not easy, but Al Gore really did the right thing.”

Lieberman spoke on the phone from Florida, where he is campaigning for the Clinton-Kaine ticket in the Jewish community of South Florida.

The former senator spoke to Jewish seniors at Palm Beach Century Village and held a roundtable with rabbis and Jewish community leaders in Palm Beach, according to the Clinton campaign. He also spoke at a shul in Broward County.

Jewish voters represent 3 to 6 percent of the electorate in Florida. Clinton is ahead by 3.8 percentage points in Florida, according to the RealClearPolitics average.

Jewish Insider has learned that Lieberman will be featured in a new highly targeted campaign kicking off this weekend by the “Jews for Progress” super PAC, aimed at Jewish voters who are still undecided or persuadable. According to a source with close knowledge of the upcoming activities, in the coming days, JFP will call more than 100,000 unique Jewish households in Florida and launch an online, email and social media campaign in an effort to replicate a successful campaign in 2012 in putting Florida in the Democratic column with the help of Jewish voters.

In an interview with Jewish Insider last year, NJDC’s chairman Greg Rosenbaum boasted that Florida ended up in the Obama column in 2012 due to a concentrated effort to mobilize Jewish voters in the Sunshine State in the last weeks leading to Election Day. An exit poll conducted by Melman showed an increase of support from 59 to 71 percent – a twelve point shift in seven weeks, which was about 144,000 additional votes. The president’s margin of victory in Florida was less than 1 percent – 70,000 votes.

Lieberman said that given how close the election is in the Sunshine State, that the Jewish vote will matter, significantly, because “turnout is generally higher among Jewish voters.”

“I think the Jewish vote will be very important here,” he said, echoing his former running mate, Al Gore, who said last week that he considers himself “Exhibit A” for the fact that every vote matters. “I offer myself as Exhibit B.”

A recent poll showed Clinton leading Trump by 43 points among Jewish voters in Florida. However, among Orthodox Jews, Trump leads Clinton 66-22 percent.

But Lieberman, a modern-Orthodox Jew, insisted that after winning three televised debates in a row, Clinton is in a position to win over many Orthodox Jewish voters. “I think the way this race is going, within the Jewish world, one of the surprising results will be that Hillary Clinton will get a much higher percentage of the Orthodox vote than a Democratic candidate has gotten for a while.”

“The modern Orthodox community is probably already trending more towards Hillary based on not only on feeling that she is a more proven, reliable and predictable supporter of Israel, but also because they are troubled by Donald Trump’s campaign,” he asserted. “I think we may be surprised to see that also happening in the ultra-Orthodox/Hasidic community. Here is the thing: she was the senator from New York for eight years. She got to know the community. And I think, generally speaking, people had a good feeling about their relations with her. She tried very hard to be supportive.”

On Israel, Lieberman said that Clinton as president “offers the hope of the Democratic Party becoming what it has been at its best – a center-left party, not a left party,” pointing to the Democratic Party’s platform. “And I think that’s the kind of party that can win, but also that can get things done for the country.”

The full interview with Joe Lieberman will be published in Jewish Insider’s Daily Kickoff on Friday.