Former US Rep. Gabrielle Giffords on stage at Democratic National Convention to deliver Pledge of Allegiance
Actress Scarlett Johansson: Why are we only speaking with half our voice when so many issues at stake here directly affect us? - live video
Vice President Joe Biden is nominated by acclamation at Democratic convention - live video
Excerpt from Obama's prepared remarks: 'It will take more than a few years for us to solve challenges that have built up over decades'
Rep. John Lewis: We must march to the polls like never, ever before - live video