Remember that it took Sandy to give Obama a boost later in October.
There were six polling firms that did polls after Sandy that also did polls in mid to late October (before Sandy). The avg before Sandy in those polls was 0.3 and after Sandy was 1.3. So Obama appears to have got a small bump, but some of those polls were also done before and after the 3rd debate (in which Obama was declared the winner in polls).
Basically from the time of the first debate in 2012 the race was pretty close to a tie all the way until election day.
Except for the week of the RNC and a couple of weeks around her Sept. 11 stumble, Clinton's margin over Trump has been greater than Obama's margin over Romney all Summer and into the Fall and that difference is only getting bigger.