or primaries

a spoiler effect happens when a losing candidate affects the results of an election simply by participating

Vote splitting is the most common cause of spoiler effects in FPP. In these systems, the presence of many ideologically-similar candidates causes their vote total to be split between them, placing these candidates at a disadvantage. This is most visible in elections where a minor candidate draws votes away from a major candidate with similar politics, thereby causing a strong opponent of both to win.

This willful ignorance of the spoiler effect is tiresome denialism of mathematics. We’ve already seen the consequences.