Former NYC Comptroller and 2009 Democratic mayoral nominee Bill Thompson is throwing his support behind Sen. Eric Schneiderman’s AG bid today, calling him “the one candidate in this field who will truly represent all New Yorkers in the fight for equal justice.”

“I’ve seen Eric in action and have no doubt that he will continue his lifelong fight for criminal justice reform, for economic fairness and for progressive change as New York’s next people’s lawyer,” Thompson said in a statement released by the Schneiderman campaign.

“Whether it’s taking on the insurance industry or ending the Rockefeller Drug laws, Eric has shown true leadership and demonstrated that he will be an Attorney General we can be proud of.”

The release plays up the fact that Thompson was the first African American to hold his former citywide post and grew up in the Bedford-Stuyvesant section of Brooklyn, became the youngest Brooklyn deputy BP and later served as president of the (now defunct) Board of Education.

Since there’s no candidate of color in the Democratic AG field, Schneiderman has been trying to position himself as the most attractive contender to represent the black and Latino communities – in part by striving to out-liberal his opponents on issues like drug law reform and redistricting.

(This hasn’t been an issue in the race, but Schneiderman is the sponsor of the controversial measure that calls for counting prisoners at their home addresses and not where they’re incarcerated).

Thompson, it should be noted, is a big supporter of AG Andrew Cuomo (he was one of several surrogates who introduced the AG at the convention in Rye earlier this summer). Cuomo has made it clear he’s not a fan of the idea of having a state lawmaker like Schneiderman or Assemblyman Richard Brodsky follow him into the AG’s office.

Thompson was floated as a potential primary challenger to state Democratic Comptroller Tom DiNapoli, whom Cuomo has not endorsed and dragged into his pay-to-play pension fund probe earlier this year.

He was also mentioned as a possible opponent to Sen. Kirsten Gillibrand, or perhaps even an LG contender, but in the end decided he would rather return to the private sector and prepare for another run for mayor in 2013.

Another interesting connection: Thompson’s 2009 campaign manager and longtime former aide, Eddy Castell, is now at the lobbying/consulting firm, the MirRam Group, and is working for Schneiderman’s opponent, Sean Coffey.