Near the closure of the elections, the chances between the two candidates becomes 50/50. So odds for Clinton will become around 2.0. Currently her odds are between 1.4/1.5. Therefore, it's a good idea to bet against Clinton to become president. You can sell your bet near the elections at 2.0.
I think it's best to bet when it's nearly couple of weeks before the election starts to make a much overview in the polls. And yes I sees it's a good idea to bet against Clinton.
Anyways is there a bitcoin gambling site where we can bet for those US presidential candidates?
Yes, you can bet on the US election at directbet.eu. Currently the odds are at 1.48 for Hillary, and 2.5 for Trump.