IMO it's easier to bet on politics than an NBA game.
Especially if that is president election. We know who is win in president election when a lot of people talk to him. From your username i know maybe we're from same country and last president election really can be predictable.
Yes, if it is like that. You will have the idea on who's the candidate that has a stronger call for its citizens. The majority will have the say and if you're following the politics that's on the list, well you're on the good timing to bet.
But if you will not analyze and listen very carefully to the pulse of the mass, you might fail as well because private companies which present surveys are seems like misguiding us on choosing the right one. As you may noticed, Pulse Asia and SWS surveys are redirecting us into a candidate which we can't believe got higher percentage than the expected bet of the majority. I am not sure whether they are paid to "promote" such candidates or not but who knows? What only we can do is become wise and don't get easily blinded by flowery words.