The Working Families Party has taken its first step to find a new ballot position for Cynthia Nixon in November, so it can move her off its line for governor and potentially give it to Gov. Cuomo.

The party filed papers to nominate Douglass Seidman — its placeholder candidate for the Assembly in Greenwich Village — for a judgeship.

That creates a landing space for Nixon, the WFP’s candidate for governor.

Under the state’s archaic election rules, the only way for Nixon to get off the WFP gubernatorial line is to die, move out of the state or run for another office.

It’s still not clear if WFP activists will go along with the plan.

The party’s state committee will meet Thursday night discuss the potential maneuvering.

The Post first reported on the WFP’s back-up plan if Nixon lost the Democratic primary to Cuomo in July.

“This is part of the process. It keeps our options open. A decision has not yet been made,” a WFP source said.

The WFP, founded by labor unions and progressives in 1998 as part of a strategy to move the Democratic Party to the left, supported Cuomo in 2010 and 2014 despite some policy disagreements.

But the relationship ruptured earlier this year when the party backed Nixon for governor.

Most of the major labor unions that bank-rolled the party — and support Democrat Cuomo’s re-election bid for a third term — then severed their ties with the WFP.

The WFP needs 50,000 votes on Nov. 6 to keep its ballot status.

Moving Nixon off the line for governor causes all kinds of complications.

Putting her on the ballot line for Assembly in the 66th district would pit her against longtime Democratic incumbent Deborah Glick, the first lesbian elected to the state Legislature. Some political insiders said raises the prospect that Nixon could defeat Glick — even if she has no intention of doing so.

Meanwhile some WFP activists are furious that the Cuomo campaign and the Cuomo-controlled state Democratic Party sent a mailer to targeted Jewish households linking Nixon to anti-Semitism.

Before the Democratic primary, WFP state director Bill Liption said he didn’t want the party to play a potential spoiler by siphoning votes from Cuomo in the general election by having a different candidate on its line, and improving the chances of Republican Marc Molinaro becoming governor.

Nixon won 500,000 votes in the Sept. 13 Democratic primary.

Former Syracuse Mayor Stephanie Miner’s name has also been mentioned as a possible Nixon replacement for governor, if Cuomo doesn’t get the line.

WFP director Bill Lipton said, “We’re focused on a member driven process to make this important decision. The state committee will make the decision.”