AS North Carolina Republicans tell it, the Obama for America volunteers stole in under cover of night and stayed, undetected — noticed belatedly only because of election results across the state.

“It was very scary,” said Chris Sinclair, a strategist for Billie Redmond, the Republican candidate for mayor in Raleigh. “You don’t know what’s going on until you wake up after Election Day and go, ‘Oh my gosh, what happened?’ ”

What happened was that candidates supported by Democrats trounced Republicans in the Raleigh and Charlotte mayoral races this fall, and even wrested control of the Wake County school board from Republicans associated with the Tea Party.

It was only after the damage was done that local party leaders learned of the hidden hand of thousands of Obama for America volunteers and staff members. Never publicizing their work, they went door-to-door across the state, successfully getting their voters out to the polls in a highly effective dry run for 2012…

The extent to which the Republicans were outhustled there was stark. Supporters of Anthony R. Foxx, who won with nearly 70 percent of the vote, made more than 200,000 calls to voters; those of his challenger, Scott Stone, made 20,000 such calls, Republican officials told The Charlotte Observer.