Mitt Romney, left, last week at the NAACP convention in New Orleans. President Obama, right, at a campaign event Saturday in Glen Allen, Va. Eric Kayne / Mandel Ngan/AFP/Getty Images hide caption

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NPR's David Folkenflik on 'Morning Edition'
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Republican presidential candidate Mitt Romney participates during the Wolfeboro, N.H., Independence Day parade on Wednesday. Kayana Szymczak/Getty Images hide caption

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Josh Rogers of New Hampshire Public Radio on 'Morning Edition'
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Wisconsin Gov. Scott Walker (R) after his victory Tuesday. Scott Olson/Getty Images hide caption

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NPR's Don Gonyea, reporting on 'Morning Edition'
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Republican presidential candidate Mitt Romney on Tuesday in Las Vegas. Justin Sullivan/Getty Images hide caption

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Ari Shapiro, reporting on 'Morning Edition'
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