Let’s say, God forbid, that happens—after the convention. Would his VP candidate automatically ascend to the Presidential candidate role? Or would there be a massive Dem fight?
Don't quote me on this, but I believe if a party-nominated candidate dies before an election, the narrow cadre of party leaders are given the power to name a replacement.
In this case, the Democrat national committee, being mostly professional and establishment Democrats, isn't going to pick a candidate wildly radical.....such as Bernie Sanders.