 President Biden has spent nearly a week at Camp David preparing for tonight, doing policy sessions and mock debates. The Biden campaign sees the debate as an opportunity to jumpstart the race. They're hoping people who haven't been paying attention will tune in, including those critical undecided voters. After the debate, the president stops by a watch party his campaign organized in Atlanta to meet with supporters. The Biden campaign says they're hosting similar events in all 50 states and 12,000 people are participating just in the battleground states. Karen Travers, ABC News.