FILE - Former President Barack Obama, with President Joe Biden and Bill Clinton, participates in a fundraising event with Stephen Colbert at Radio City Music Hall, Thursday, March 28, 2024, in New York. Obama and former first lady Michelle Obama have endorsed Kamala Harris in her White House bid, giving the vice president the expected but still crucial backing of the nation’s two most popular Democrats.(AP Photo/Alex Brandon, File)

FILE - Democratic presidential candidate, Sen. Barack Obama, D-Ill., gives his acceptance speech at the Democratic National Convention at Invesco Field at Mile High in Denver, Aug. 28, 2008. (AP Photo/Alex Brandon, File)

FILE - President Barack Obama stands on stage after addressing the Democratic National Convention in Charlotte, N.C., Sept. 6, 2012. (AP Photo/J. Scott Applewhite, File)

FILE - Democratic presidential candidate, Sen. Barack Obama, D-Ill., hugs his wife, Michelle Obama, after giving his acceptance speech at the Democratic National Convention at Invesco Field at Mile High in Denver, Aug. 28, 2008.(AP Photo/Alex Brandon, File)

FILE - President Barack Obama addresses the Democratic National Convention in Charlotte, N.C., Sept. 6, 2012. (AP Photo/J. Scott Applewhite, File)

FILE - Democratic presidential candidate Sen. Barack Obama, D-Ill., waves with his family and his running mate's family after his acceptance speech at the Democratic National Convention at Invesco Field at Mile High in Denver, Aug. 28, 2008.(AP Photo/Alex Brandon, File)

FILE - President Barack Obama addresses the Democratic National Convention in Charlotte, N.C., Sept. 6, 2012. (AP Photo/David Goldman, File)

FILE - Democratic presidential nominee Sen. Barack Obama, D-Ill., left, and his running mate, Sen. Joe Biden, D-Del., wave after Obama's acceptance speech at the Democratic National Convention, Aug. 28, 2008, in Denver. (AP Photo/Ron Edmonds, File)