Key stakeholders in the Working Families Party have sent a letter to fellow committee members on behalf of Sen. Eric Schneiderman, calling him the “only choice” to receive the labor-backed party’s endorsement in the AG’s race.

The letter is signed by Citizens Action’s Karen Scharff, 1199’s George Gresham, 32BJ’s Mike Fishman, 52nd AD District Leader Dorothy Siegel (treasurer of the WFP since Mike McGuire resigned amid the whole DFS mess), and the Long Island Progressive Coalition’s Lisa Tyson – all of whom have endorsed the Manhattan Democrat’s statewide bid.

“Eric is, and always has been, a proud member of what Paul Wellstone called ‘the Democratic wing of the Democratic Party,'” the group writes.

“He’s not afraid to stand up for unions, for the rights and dignity of working people, for the critical role of the public sector in providing a social safety net and reining in the excesses of the market.”

“And he’s always been a vocal opponent of discrimination of any kind, whether it’s against people of color, women, gays, lesbians, and transgender people, immigrants, seniors or people with disabilities.”

The group plays up the whole “true progressive” angle very hard, which has become something of a hallmark of Schneiderman’s campaign.

He’s sticking with the conventional wisdom that the bulk of the Democratic primary vote comes from left-of-center voters, although I have heard that idea debunked by several of his opponents, who argue it’s more of a Manhattan strategy that a five-borough approach.

While Schneiderman might have the support of the WFP’s more left-leaning members, he does not have a lock on the party’s affiliates.

RWDSU has endorsed Nassau County DA Kathleen Rice, while CWA – another major WFP player – has backed Assemblyman Richard Brodsky.

The takeaway here is there’s still no clear labor favorite for AG, which could prove difficult when the WFP tries to make an endorsement.

Like other parties, it takes 25 percent of the weighted WFP vote to get on the ballot, but all non-enrolled candidates need 50 percent of the state committee or the executive committee to get a Wilson Pakula. It’s possible that none of the Democratic candidates makes the cut, but party insiders say it’s unlikely leadership would want the line to go blank.

WFP SCM Letter Final