Biden is best when talking to a union hall in Ohio or Pennsylvania, but this debate will be watched by undecided swing voters across the nation. That's the audience Biden has to reach and resonate with in an effort to shift momentum away from Team Mitt and bring passion, clarity and contrast back to the Obama campaign.
John Avlon is a senior political columnist for Newsweek and The Daily Beast. He is co-editor of the book "Deadline Artists: America's Greatest Newspaper Columns." He is a regular contributor to CNN's "Erin Burnett OutFront."
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