It's obvious for several reasons that political polling is at best nonsense and worst outright fraudulent. Reason 1: people don't change their voting intentions much. So how can polls swing one way and the other so much? Answer must be that they are measuring noise. Reason 2: headline numbers aggregate several polling results, but apparently don't discard known fraudulent data from partisan polsters. So the results can be trivially changed by simply spending money. Reason 3: nobody sane responds to a polster. So they are measuring data from provably insane people. Reason 4: polsters often exclude samples that should be included, for example by requiring respondents to have voted in two previous elections. So the samples is skewed. And on and on. Add to this the incentives in the news industry to make things click worthy and you have the result we observe. Nobody wants to say the emperor has no clothes. There's also a bias in some media to report a close race for fear of being accused of influencing the outcome.