Well, it’s official (almost). Congressman Joe Sestak is set to officially announce his candidacy for the Democratic nomination for Arlen Specter’s Senate seat. But with Specter racing towards an EFCA compromise and with the backing of just about every Democrat in Pennsylvania, Sestak’s chances look grim. Nevertheless, the Washington Post points out that labor unions could quickly build Sestak a formidable grassroots network.

Specter’s opposition to the Employee Free Choice Act when he was a Republican set him at daggers drawn with organized labor. Now that he is a Democrat, however, Specter is trying to find a way to get right with labor — understanding that the grassroots power that unions bring could be just the sort of thing Sestak needs to build a statewide organization on the cheap. Most national labor operatives believe Sestak Specter will find a way to be for whatever the re-written version of EFCA looks like, cutting off Sestak’s oxygen with labor. If Sestak can keep labor neutral — not likely, according to incoming AFL-CIO president Richard Trumka — it would amount to a major victory for the challenger.