Does free speech cover a poll asking whether someone wants a public figure assassinated?

Yes - The poll doesn't incite. It asks opinion. Someone responds "he should be assassinated;" that is an opinion, not a threat. The poll-owner didn't incite. The affirmative respondent didn't threaten.

No - It's not free speech because the question incites a violent crime and the answer threatens someone's life.

Undecided - I am unsure if such a poll would meet the legal requirements for an incitement and/or a threat, so I am unsure whether the poll could attract free speech protection.