There is already plenty of historical data that would have demonstrated the quality of the predictions. This specific bet, however, could be the worst way to judge the prediction markets given that the key demographics of the gamblers, young risk taking males, are the same that strongly favor the GOP candidate. In that regard, your bet alone demonstrates loyalty which feels like a soft win. Also, when you win if you win, and if you lose, you were still right because you can cite the heavily skewed prediction market as proof the election was stolen.