 But we are not going to let that happen. Trump's campaign said Wednesday it won't agree to propose dates for a vice presidential debate until at least the Democratic National Convention, which is scheduled to begin August 19th. That's because the Trump camp claims they don't know who the nominee will be, pointing to calls for Joe Biden to drop out. Harris also weighed in on the assassination attempt against Trump, speaking before a moderated conversation on abortion access in Kalamazoo. As we all know, it was a heinous, horrible and cowardly act.