 His support for President Biden, something the White House has been looking for, as calls for Biden to step aside continue. ABC's Mary Bruce with more on the defiant stand being taken at the White House. We really saw a dramatic shift in tone from the president yesterday. He is coming out not just defiant, but aggressively fighting back, adamant that he is not going anywhere and going a step further, challenging his Democratic doubters, expressing frustration by those in the party who are calling on him