Obama aide: How Clinton may have won

[David] Plouffe served as Obama’s campaign manager and is often referred to as the"unsung hero" of the president-elect's White House bid. He was largely responsible for designing the strategy that ultimately dashed Clinton's own ambitions for the Oval office.

Now, the camera-shy Plouffe is revealing what surprised him the most about Clinton’s campaign: the New York senator's strategists willingness to concede a string of caucus states to the Obama camp. In the process Obama won a vast sum of delagates and created a lead in the delegate count that ultimately proved fatal to Clinton's chances.

"We were surprised because at some point it became likely that it was going to be a battle that went on for some time, and delegates that are gained through a caucus are no different than through a primary—so every contest mattered," Plouffe told Portfolio Magazine.