You build your own polling average for an election, adjusting each poll for known pollster bias ('house effects'), how recent it is, and sample size, to get a cleaner probability than any single poll. You then trade whenever the Polymarket price drifts away from your model's number. The edge is having a sharper, faster-updating estimate of the race than the crowd, and acting each time a new poll moves your average but the market hasn't caught up.
Markets on Polymarket where polling aggregator edge (elections) is the natural play:
