text:  from ABC News. I'm Sheri Preston. For the first time ever, a sitting U.S. president will be debating a former U.S. president for another term in the White House. President Joe Biden and former President Donald Trump swearing off tonight in Atlanta. ABC political director Rick Klein has more on expectations going into the event. We asked voters in this poll, who do you think is going to do a better job? What kind of performance are you expecting? And frankly, voters think both of them are going to do a pretty lousy job, but they think...