“Can the party really substitute a different candidate without calling another convention?”
nothing in the Constitution about parties OR conventions.
It’s a state-by-state issue, since there is no national election.
Some states may have laws that allow a swith, but if a state has a filing deadline that has passed, DNC would need to go to that state’s courts.
Mondale was locked in, he knew he was toast long before chad time. Dukakis, too. Kerry and Gore were sure they’d win, so the issue never came up.
As far as this election, the hen must sit a while before we enumerate the progeny.
bttt