see more

PHILADELPHIA, PA - JULY 27: US Vice President Joe Biden reacts to the crowd as his wife Jill Biden, looks on after delivering remarks on the third day of the Democratic National Convention at the Wells Fargo Center, July 27, 2016 in Philadelphia, Pennsylvania. Democratic presidential candidate Hillary Clinton received the number of votes needed to secure the party's nomination. An estimated 50,000 people are expected in Philadelphia, including hundreds of protesters and members of the media. The four-day Democratic National Convention kicked off July 25. (Photo by Joe Raedle/Getty Images)

PHILADELPHIA, PA - JULY 27: US Vice President Joe Biden reacts to the crowd as his wife Jill Biden, looks on after delivering remarks on the third day of the Democratic National Convention at the Wells Fargo Center, July 27, 2016 in Philadelphia, Pennsylvania. Democratic presidential candidate Hillary Clinton received the number of votes needed to secure the party's nomination. An estimated 50,000 people are expected in Philadelphia, including hundreds of protesters and members of the media. The four-day Democratic National Convention kicked off July 25. (Photo by Joe Raedle/Getty Images)
Getty Images

Getty Images News Joe Raedle

see more

CHARLOTTE, NC - SEPTEMBER 06: Democratic vice presidential candidate, U.S. Vice President Joe Biden stands with his wife Second lady Dr. Jill Biden and family after being nominated during the final day of the Democratic National Convention at Time Warner Cable Arena on September 6, 2012 in Charlotte, North Carolina. The DNC, which concludes today, nominated U.S. President Barack Obama as the Democratic presidential candidate. (Photo by Alex Wong/Getty Images)

CHARLOTTE, NC - SEPTEMBER 06: Democratic vice presidential candidate, U.S. Vice President Joe Biden stands with his wife Second lady Dr. Jill Biden and family after being nominated during the final day of the Democratic National Convention at Time Warner Cable Arena on September 6, 2012 in Charlotte, North Carolina. The DNC, which concludes today, nominated U.S. President Barack Obama as the Democratic presidential candidate. (Photo by Alex Wong/Getty Images)
Getty Images

Getty Images News Alex Wong

see more

WASHINGTON, DC - JANUARY 21: U.S. Vice President Joe Biden and Dr. Jill Biden wave goodbye after dancing during the Comander-in-Chief's Inaugural Ball at the Walter Washington Convention Center January 21, 2013 in Washington, DC. Biden and President Barack Obama each took their oath of office earlier in the day. (Photo by Chip Somodevilla/Getty Images)

WASHINGTON, DC - JANUARY 21: U.S. Vice President Joe Biden and Dr. Jill Biden wave goodbye after dancing during the Comander-in-Chief's Inaugural Ball at the Walter Washington Convention Center January 21, 2013 in Washington, DC. Biden and President Barack Obama each took their oath of office earlier in the day. (Photo by Chip Somodevilla/Getty Images)
Getty Images

Getty Images News Chip Somodevilla

see more

WASHINGTON - JANUARY 30: (AFP OUT) U.S. President Barack Obama (L) greets Vice President Joe Biden (C) and his son Hunter Biden as they attend the game between the Duke Blue Devils and Georgetown Hoyas on January 30, 2010 at the Verizon Center in Washington, DC. (Photo by Alexis C. Glenn-Pool/Getty Images)

WASHINGTON - JANUARY 30: (AFP OUT) U.S. President Barack Obama (L) greets Vice President Joe Biden (C) and his son Hunter Biden as they attend the game between the Duke Blue Devils and Georgetown Hoyas on January 30, 2010 at the Verizon Center in Washington, DC. (Photo by Alexis C. Glenn-Pool/Getty Images)
Getty Images

Getty Images Sport Pool

see more

Democratic vice presidential nominee Joe Biden points to his mother Jean Finnegan Biden on stage during the Democratic National Convention 2008 at the Pepsi Center in Denver, Colorado, on August 27, 2008. AFP PHOTO / Paul J. RICHARDS (Photo credit should read PAUL J. RICHARDS/AFP via Getty Images)

Democratic vice presidential nominee Joe Biden points to his mother Jean Finnegan Biden on stage during the Democratic National Convention 2008 at the Pepsi Center in Denver, Colorado, on August 27, 2008. AFP PHOTO / Paul J. RICHARDS (Photo credit should read PAUL J. RICHARDS/AFP via Getty Images)
Getty Images

AFP PAUL J. RICHARDS