The most likely scenario is Trump/Vance are still selected by the Electoral College but on election day Vance is sworn in as President, without a Vice President. Vance then goes through the standard process (Senate approval) to select a Vice President.
Technically it is possible for the Electoral College to select Vance and whomever Vance selects as VP. Since Republicans (will) have control of the Senate the odds of this scenario is slightly increased just to save everyone time. However given the various Electoral College deadlines and the fact that Vance would likely want time to select a VP, this option isn’t likely.
Now if Trump had died 4 weeks before election day and Vance had clearly selected a new VP already, then the second scenario is more likely.
The most likely scenario is Trump/Vance are still selected by the Electoral College but on election day Vance is sworn in as President, without a Vice President. Vance then goes through the standard process (Senate approval) to select a Vice President.
Technically it is possible for the Electoral College to select Vance and whomever Vance selects as VP. Since Republicans (will) have control of the Senate the odds of this scenario is slightly increased just to save everyone time. However given the various Electoral College deadlines and the fact that Vance would likely want time to select a VP, this option isn’t likely.
Now if Trump had died 4 weeks before election day and Vance had clearly selected a new VP already, then the second scenario is more likely.