Obama's Presidency; Democratic National Convention, Night Two; Frank Luntz

Authors Jodi Kantor and David Maraniss talk about who Barack Obama is, his dynamic with his wife, and how he has changed throughout his presidency. Dan Balz of The Washington Post and E.J. Dionne, author of "Our Divided Political Heart," provide an analysis of night two of the Democratic National Convention. Frank Luntz, former Republican strategist and pollster, discusses the Democratic National Convention and gives his sense of the presidential race based on focus groups and surveys.