(CNN) -- Now the Democrats are stepping into the spotlight. With the Republicans packed up from their stormy convention in Tampa, Florida, and back on the campaign trail, the Democrats gather in Charlotte, North Carolina, to explain to Americans why their candidate is a better choice in November. Like Republicans, Democrats must use this high-visibility media opportunity to outline their arguments for the fall. Although President Barack Obama is more of a known commodity than GOP candidate Mitt Romney after three and a half years in the White House, there is still a lot of work for Democrats to do in the coming days.
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Democrats hold their political convention this week in Charlotte, North Carolina
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Julian Zelizer says it's vital that Democrats respond to the charges made by the GOP
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He says Obama can't rely on blaming Bush or warning what a Romney White House would do
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Zelizer: Obama should strongly defend his record, including stimulus, health care law
With Republicans talking about failed leadership, @placeholder must seek to show this is not the case.