I don't know if anyone will change his or her vote, but turnout could be crucial in the swing states. Trump has all the enthusiasm now, whereas Democrats are demoralized because they're practically leaderless, given Biden's cognitive decline and inability to connect with reality or to communicate a compelling vision and case against Trump. There's also the fact that at least a third of Americans don't vote, so they're open to being swayed. According to some reporting, Trump is leaning towards affecting a more unifying, compassionate, messianic pose at the Convention.