The latest issue of TIME offers more ammunition for that view, in the second paragraph of this Michael Scherer article:

[I]f you want to find out why the President has set up shop in a Chicago skyscraper 18 months before Election Day, you need only peek into the office of Jeremy Bird, 32, the campaign’s field director, at the far end of the room. He pulls a name from a database on his laptop, picks up his phone and dials in the hope of reminding one more person of the 2008 magic. “I just wanted to call, and first I wanted to thank you,” Bird says when a volunteer from Obama’s first presidential campaign answers in North Carolina. The computer screen notes that this guy hasn’t done much in recent years, so Bird asks for his thoughts about 2012. “You are listed as a superstar 2008 volunteer,” Bird continues. “What do we need to do to get you back involved?”