To add on to what @halcyoncmdr@lemmy.world said, you need to change the voting system first before that becomes viable, and then it happens naturally without any manual intervention.

Take the Alaska 2022 election as an example. Before, candidates had to be extreme in order to appeal to their base, as all that mattered was making the other side look “evil”. Once they switched to rank voting, all of a sudden they had to convince voters of their own worth so they’d be put in at least second or third place, if not first directly. It also meant people could safely vote third party or alternative candidates within the major parties without a spoiler effect, as if the candidate is unviable, the vote just gets transferred to the second place pick.

Tl;Dr: The real solution to what you’re trying to do is abandon first past the post and adopt some kind of ranked choice voting.