"Joe would make a great president," she said. "Last time, when he ran, I supported him. I wanted us out of Iraq and I felt Joe would do that, but Barack [Obama] did it, so everything has worked out."
Focused on supporting President Obama's re-election efforts, she admitted she did not know if this would be the final campaign for her 69-year-old husband.
"We're focusing on this campaign and winning this campaign. I take one campaign at a time," she said.
Dr. Biden appeared on the program to promote her new children's book, "Don't Forget, God Bless Our Troops."
Notable deaths of 2014 [PHOTOS]
Marine detained in Mexico is 'highly despondent'