Nate Silver recently offered to bet $100,000 against Keith Rabois that Trump would not win Florida by 8 or more points:

Will this bet actually happen? Resolves YES when both parties confirm that the loser has paid the winner at least $100,000, or credible reporting confirms this fact.

Resolves NO when:
-Either party backs out of the bet before signing a legally binding contract (or something equivalent), and does not "rejoin" the bet within a week of backing out
-A party is able to avoid paying even after signing a contract.
-Discussion of this bet between Silver and Rabois dies off before the bet is finalized-i.e. one of them doesn't respond to or talk about the bet for a week.
- They keep talking about it until the election, but a contract/whatever isn't finalized and the loser doesn't pay out.

I will not bet on this market. If something happens that falls outside the stated conditions, I will use my judgement to resolve the market in the way that best matches the question in the title.