The attempt does not have to be successful, but it needs to involve some effort and political capital; not just a throwaway comment here and there.

Resolves based on my own judgement of what counts as "a serious attempt". I won't bet.

(The January 6th shenanigans and constant accusations of voter fraud last time were severe enough to count under this criterion.)

Resolves N/A if he dies before the last year of his term, and he has not already done something that would qualify.