It’s a possible scenario if Trump runs an independent or 3rd party Bid. No three candidates in this election other than Hillary(D), Trump(I), Cruz(R), in this scenario would be a a good bet. In other words you could wager a small amount for big payout.
On the other hand Hillary can get indicted, Cruz could be found in bed with a 14 year old boy of no particular race and Trump could run of with Megyn Kelly. Events so unlikely that you could never receive an adequate payout.
Not really likely, because of ballot access laws. Many states like Texas have "sore loser" laws. It is not possible to get on the ballot in many states if a candidate loses a party nomination but was a candidate in the primary. If the Republican race goes to the convention, all the states will have had primaries or caucuses. Whoever does not get the nomination will be barred from being on the ballot in most states.
Not really likely, because of ballot access laws. Many states like Texas have "sore loser" laws. It is not possible to get on the ballot in many states if a candidate loses a party nomination but was a candidate in the primary. If the Republican race goes to the convention, all the states will have had primaries or caucuses. Whoever does not get the nomination will be barred from being on the ballot in most states.