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CHARLOTTE, N.C. - President Obama came into the Democratic National Convention his own worst enemy, with memories of 2008 haunting him every bit as much as anything Mitt Romney can say about him.

Obama did not quiet those echoes this week. His candidacy and his convention speech sought to leverage the powers of the incumbency, but those kept the candidate from soaring like he did four years ago.

The president offered an optimistic speech - rising above the political process, knitting together an agenda, and lifting up the choices as broadly as he could.

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Yet the marching orders he issued to his faithful - "to rally around a set of goals for your country" - were better suited to a challenger than an incumbent. They may be what the Obama army needed to hear - in 2008.

The central challenge of the president's campaign, to push "forward" while explaining the misses of the last four years, remains unresolved.

The president implored his audience to not "buy into the cynicism" of believing change isn't possible. The nation, though, has grown skeptical of its future, and perhaps of its president.