Joe Biden has made his presidential campaign all about one man: Donald Trump. Indeed, the presumptive Democratic presidential candidate has said very little about what he’s campaigning for, but a lot about who he’s campaigning against.

The goal is to make the November election a referendum on Trump, which Democrats seem to think is a winning strategy. Convince voters that Biden is the only thing standing in between them and four more years of Trumpian chaos, and they’ll turn out for a candidate who still draws little enthusiasm from his own party.