The magic of '08 has been replaced by apathy typical in midterm elections. But Obama's foot soldiers, using a personal approach, are working hard to keep Democrats in power. Two years after President Obama's historic election, echoes of the grass-roots campaign that put him over the top in battleground states like Minnesota can still be heard on the University of Minnesota campus. "Fired up?" shouts youth coordinator Mike Griffin, a staffer with Organizing for America, the street division of the Democratic National Committee (DNC), sometimes dubbed Obama's Army. "Ready to go!" comes the reply from a gaggle of volunteers with...