With Senate Democrats getting closer to thwarting a GOP override vote on the Iran deal, and with House Democrats increasingly showing their own strength in upholding a presidential veto, one constituency remains a key focus in the public relations battle over the Iranian nuclear agreement: Jewish Democrats.  

On Friday, six Jewish House Democrats sent a letter to colleagues pointing out the so-called Joint Comprehensive Plan of Action has their support and support from a number of former Jewish members. The “Dear Colleague” letter directs Democrats to a New York Times ad in which 11 former Jewish members endorsed the agreement on Thursday. “During our many collective years in Congress,” the 11 erstwhile members wrote, “we unwaveringly supported Israel, led or co-sponsored every major piece of legislation to strengthen the U.S.-Israel relationship and stood at the forefront of every major piece of sanction law designed to halt Iran’s pursuit of nuclear weapons. We support the international nuclear weapons agreement between the P5+1 nations and Iran.”  

The letter included the signatures of former Sen. Carl Levin, D-Mich., and former Rep. Barney Frank, D-Mass.  

While it appears both the House and Senate will be able to uphold President Barack Obama’s veto of a disapproval resolution that would block the deal — the Senate may even be able to filibuster the resolution — the public relations battle over the deal rages on.  

Perhaps the biggest PR blow to the agreement came when Sen. Charles E. Schumer, the No. 3 Democrat in the Senate who is expected to lead the caucus starting in 2016, came out in opposition to the deal. The hearts-and-minds campaign hit another significant snag when another Jewish New York Democrat, Rep. Steve Israel, announced his disapproval of the deal.  

But despite the Schumer and Israel defections, almost every day another Democrat comes out in support of the deal — and the White House and Democratic leadership have been touting backing of the agreement among a number of other Jewish Democrats, proving, they say, that the deal is in the best interest of Israel.  

Israeli Prime Minister Benjamin Netanyahu has steadfastly opposed the deal, but support from congressional Democrats who are Jewish has been key in signaling to other Democrats that backing the nuclear agreement isn’t toxic.  

The Senate is expected to take up a resolution of disapproval on the Joint Comprehensive Plan of Action as soon as lawmakers get back from August break, and the House is expected to follow suit soon after.