MoveOn, a giant in the progressive political world and an early endorser of Barack Obama in 2008, warns that it might have to “pull the plug” on key campaigns to help Obama and Senate Democrats if its 7 million members don’t pony up with at least $5.

Without a rush of new cash, MoveOn says it will have to give up efforts to elect Elizabeth Warren in Massachusetts, help the recall fight against Wisconsin Gov. Scott Walker, and energize younger voters who’ve soured on Washington.