Now the debate Tuesday night — hosted by ABC News at Philadelphia's National Constitution Center — has become the first showdown between Harris and Trump, who both agreed to move forward with it after weeks of back-and-forth about the event's specifics. The debate begins at 9 p.m. Eastern Time on Tuesday, Sept. 10.

Vice President Kamala Harris and former President Donald Trump are both traveling to swing states, kicking their campaigns back in full gear after Tuesday's debate.