WASHINGTON — There have been letters signed by generals, rabbis, Hollywood folks, and now – as of Thursday morning – a New York Times advertisement signed by a who’s who of Jewish “formers,” 25 mostly erstwhile members of the A-list of American Jewish leadership avowing their support for the Iran nuclear deal.

The prominent newspaper carried a full-page ad, sponsored by a group called the “No Nukes for Iran Project,” which urged Congress to support the Joint Comprehensive Plan of Action (JCPOA), an agreement between Tehran and six world powers to check Iran’s nuclear program in exchange for international sanctions relief.

The clock is ticking for the Obama administration to enlist the support of enough members of Congress to sustain a presidential veto on what is expected to be a Congressional vote of disapproval on the controversial nuclear deal.

The advertisement noted that many of the signers have “devoted decades to building and enhancing Israel’s security and strengthening the US-Israel alliance,” a statement designed to counter claims by some on the American right that no supporter of Israel could endorse the agreement, which Israeli leaders on left and right strongly oppose.

It begins by quoting former Israeli Navy commander and Shin Bet head Ami Ayalon, who said that “when it comes to Iran’s nuclear capability, this [deal] is the best option” among those actually available to the international community.

“We agree with Admiral Ayalon and leading Israeli military, scientific and intelligence experts who share this view,” the signers wrote.

Ami Ayalon in 2008 (photo credit: Olivier Fitoussi /Flash90)

Ami Ayalon (Olivier Fitoussi /Flash90)

“Each of us has devoted decades to building and enhancing Israel’s security and strengthening the US-Israel alliance. Our commitment to Israel is everlasting.”

The signers noted that they “remain deeply concerned that Iran is unflinchingly anti-Semitic and an unapologetic state-sponsor of terrorism,” but added that “a nuclear-armed Iran would be even more dangerous. While not perfect, this deal is the best available option to halt Iran’s nuclear weapons program.”

They concluded by “strongly urg[ing] Congress to support the Iran agreement.”

Congress is in the middle of a 60-day review period of the deal, which was signed between Iran and the P5+1 states last month. Congress’s Republican leadership will have Congress vote on a resolution of disapproval which, if passed, could force the US to pull out of some of its sanctions relief obligations under the agreement.

The administration is seeking to secure a large enough number of Democratic supporters to sustain a presidential veto of the resolution – which Congress can only override with a two-thirds vote in both chambers – and the battle for individual votes in the Senate has proven to be one of the key political dramas in President Barack Obama’s second term.

Both sides have pressured and cajoled undecided lawmakers.

A number of the people who signed the declaration are former heads of organizations that have come out swinging against the controversial deal, including former AIPAC executive director Thomas Dine and former American Jewish Committee presidents E. Robert Goodkind, Robert S. Rifkind, and ex-ambassador Alfred H. Moses.

The list also includes three former chairs of the Conference of Presidents of Major American Jewish Organizations, two Jewish former members of Congress and nine leaders from the Jewish Federations of North America.

The signers stressed that they were signing as individuals rather than as representatives of the organizations that they formerly headed.

Only two signers — S. Daniel Abraham, the chair of the eponymous S. Daniel Abraham Center for Middle East Peace, and National Jewish Democratic Council Chairman Greg Rosenbaum – presently hold their leadership positions.

Thursday’s letter is the latest in a series of signed missives intended to show high levels of support for the Iran deal in specific sectors. In recent weeks, similar public letters have been released in support of the deal by rabbis, prominent scientists, retired military officers and Hollywood figures.

The two most recent such letters – Thursday’s and the rabbis’ letter, which came out three days ago – are touted by promoters as proving that the US Jewish community is far from universally opposed to the nuclear accord.