I’m not so sure that he can be. He was nominated by Trump, and the party as a whole voted on both Trump and Vance, together. Would they need a new convention in order to select a new VP? I don’t know. I don’t think that anything like that has ever happened before, so it would be uncharted territory. Much like if the VP died in office.
They could always say that JD is officially on the ticket, but he is going to resign day 1 and let RFK Jr. have the job…
I’m not entirely sure that the president can simply appoint a new VP once they’re in office, since VP is an elected position.
It’s a fascinating question, and I hope that there’s never any reason to see it answered.
VP can resign at any time though. I’d have to double check, but I don’t think there is a line if succession for the VP, since the President is over the VP, they can just select a new VP, although Congress may have to have a majority vote to accept the appointment.
Now to go check how good my HS government class was almost 20 years ago…
Edit : 25th Amendment, Section 2
Whenever there is a vacancy in the office of the Vice President, the President shall nominate a Vice President who shall take office upon confirmation by a majority vote of both Houses of Congress.
I actually can’t find anything (quickly) about when/how the VP can resign, but I assume they would have to formally submit their resignation in writing, or verbally and directly to the President, who would accept the resignation. As far as I can tell, the VP could resign right after being sworn in.
Agnew resigned. Nixon nominated Ford to replace. Congress approved the nomination. Ford became vp and became president when Nixon resigned. Ford repeated the process FOR whomever he selected for VP.