DES MOINES, Iowa -- With less than six months until the caucuses, Iowans expect to receive plenty of cold calls from presidential campaigns. However, getting a call from a candidates son is enough to stop them in their tracks.

In an office in downtown Des Moines buzzing with dozens of simultaneous conversations, campaign staffers and volunteers hover over laptop computers, updating Iowans on former Maryland Gov. Martin OMalleys (D) most recent campaign events in their area. Among them, a young man in a bright blue button down shirt dials a phone number from an Excel spreadsheet, flashing a smile before putting an iPhone to his ear.