[cnn-photo-caption image=http://i2.cdn.turner.com/cnn/2009/POLITICS/02/26/preston.accountability.now/art.moulitsas.cnn.jpg caption="DailyKos' Markos Moulitsas says his online community is wary of Democrats being corrupted by power."]
WASHINGTON (CNN) - Call it a shot fired across the bow, or simply a stern warning to congressional Democrats: Power corrupts, and we are watching your every move. And if we think you are no longer representing the interests of your constituents, we will try to defeat you next year.
A Republican threat? Good guess, but no.
This is what Democratic activists are telling lawmakers of their own party, and they have formed a political action committee to raise money and help galvanize support for Democratic primary challengers in 2010.
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Accountability Now PAC formally launched Thursday, creating a potential headache for Democratic leaders who would rather spend time focused on expanding their congressional majorities next year rather than defending Democrats from fellow Democrats.