Final tracking poll of the day is out

The Washington Post/ABC Tracking Poll is out. They find that while Obama's lead increased by one point from yesterday, McCain's declined by a point:

Obama 54
McCain 43

The spread yesterday was 53-44. The Post observed:

One part of McCain's steep challenge is that more than a quarter of the probable electorate has already voted - among these early birds, 59 percent said they voted for Obama, 40 percent for McCain.

Today's numbers were these:

Rasmussen, Obama +5
Hotline, Obama +5
Zogby, Obama +6
Research 2000/Daily Kos, Obama + 7
Gallup Expanded Likely Voter Model, Obama +8
Washington Post/ABC, Obama +11

Talking Points Memo observes:

Adding these polls together and weighting them by the square roots of their sample sizes, Obama is ahead 51.5%-44.2%, a lead of 7.3 points, compared to the 51.2%-44.1% Obama lead from yesterday. Counting today, Obama's lead has increased by small amounts in the last four consecutive Composites.