Of course, many watched from home, but some chose to head out to the bar for a more interactive experience.
Crowds gathered Tuesday night at the City Tap House in Philadelphia for a nonpartisan watch party.
"We do a lot of sports, but to do the debate, it's very different but it's exciting. It's something new," said Yasmine Harris, City Tap House's front-of-house operational manager.
The party was organized by several nonpartisan civic organizations, including the League of Women Voters of Philadelphia and the Committee of Seventy. Organizers say watching a debate with others is a totally different experience.
"We all recognize how important Philadelphia and Pennsylvania will be in the fall to give people a place to come in a nonpartisan environment to talk across their differences," said Lauren Cristella, the president and CEO of the Committee of Seventy.
The topics ranged from the economy to abortion to the southern border.
There were other watch parties organized by partisan organizations, too.
Mayor Cherelle Parker and other Philadelphia Democrats watched the debate at the Dell Music Center and the Philadelphia Young Republicans gathered at the Kimpton Hotel Monaco in Old City.
At Temple University, college students also studied the debate closely.
"For the first time for many students, this is the first time they're voting and so we want to impart to be engaged, to stay informed and to be a part of the political process," said David Mindich, the professor of journalism at Temple University.