
Vice President Joseph R. Biden speaks in Las Vegas on Saturday on an audience member’s cellphone at the national convention of the Disabled American Veterans, which he addressed on behalf of the campaign. (Associated Press)

Vice President Joseph R. Biden addresses the annual convention of the National Association for the Advancement of Colored People on July 12 in Houston. Mr. Biden has been dispatched by the Democratic ticket’s presidential campaign to shore up support with the party’s various constituencies and interest groups. (Associated Press)

“[Romney] reflexively criticizes the president’s policies without offering any alternatives. When he does venture a position, it’s a safe bet that he previously took exactly the opposite position and will probably change his mind again and land in the wrong place — far out of the mainstream. Or he mischaracterizes our record to create a nonexistent contrast.” - Vice President Joseph R. Biden (Associated Press)

“[Romney] reflexively criticizes the president’s policies without offering any alternatives. When he does venture a position, it’s a safe bet that he previously took exactly the opposite position and will probably change his mind again and land in the wrong place — far out of the mainstream. Or he mischaracterizes our record to create a nonexistent contrast.” - Vice President Joseph R. Biden (Associated Press)

Vice President Joseph R. Biden addresses the annual convention of the National Association for the Advancement of Colored People on Thursday, July 12, 2012, in Houston. (AP Photo/Pat Sullivan)

Vice President Joseph R. Biden addresses the annual convention of the National Association for the Advancement of Colored People on Thursday, July 12, 2012, in Houston. (AP Photo/Pat Sullivan)

Vice President Joseph R. Biden has been filling in for President Obama at speaking engagements recently, including at the National Educational Association annual meeting last week (top), disappointing one of the country's largest unions and the earliest labor group to endorse Mr. Obama. His visits smaller venues such as the Center for Active Seniors during a campaign stop of Davenport, Iowa. (The Quad City Times via Associated Press)

** FILE ** Vice President Joseph R. Biden salutes after arriving to speak before the 2012 National Educational Association's annual meeting on Tuesday, July 3, 2012, in Washington. (Associated Press)

An Obama campaign T-shirt recalls an off-mic comment by Vice President Joseph R. Biden about the Affordable Care Act. (ObamaForAmerica.com)