Political newcomer Dan Squadron has landed himself a powerful institutional supporter in his quest to oust incumbent Sen. Marty Connor in next Tuesday's 25th SD Democratic primary.

Health care workers union 1199 SEIU has quietly endorsed Squadron over Connor, whom it backed in 2006 over Ken Diamondstone, and is pulling out all the stops on his behalf.

That includes four mailers, including the one below that touts his grandparents' immigrant roots, his family ties to the ACLU and his experience as a "lifelong community advocate" (good thing they didn't say community organizer!)

The union has also made live voter ID calls for Squadron and will be making GOTV calls for him on primary day.

Connor has wracked up far more endorsements than Squadron in this race - landing the support of everyone from the AFL-CIO and Citizens Union to Council Speaker Christine Quinn and his fellow members of the Senate Democratic conference (the same people who ousted him from the minority leader's post in 2002 in favor of David Paterson).

But Squadron has some heavy-hitting allies of his own, including, of course, his former boss Sen. Chuck Schumer, Mayor Bloomberg, the Working Families Party and now 1199, which, with a few exceptions like this race and Councilman Hiram Monserrate's run in the 13th SD, is spending most of its money this fall helping its longtime allies, the Senate Republicans, in their battle to keep the majority.

The union will, however, be helping a select group of Democratic primary candidates next week, including: Assembly Speaker Sheldon Silver, Assemblyman Adriano Espaillat, Assemblyman Sam Hoyt, Assemblyman Phil Ramos, Sen. Kevin Parker, Councilman Mike McMahon (13th CD), Sen. Shirley Huntley and Jon Powers (26th CD).

Interesting missing name from that list: Rep. Ed Towns, who is facing a tough primary challenge from Kevin Powell.