I think that’s where the suggestion of ranked choice voting comes in. Because even a principled, well-meaning 3rd party candidate can only act as a spoiler in the current system, and the Democratic Party isn’t wrong to point that out.
In a toss-up election like this one with razor-thin margins many people will say afterwards “this small sliver of voters motivated by issue X is what put the winner over the top!” And, regardless of the issue they’re talking about, they’re probably going to be right.
