This hasn't been the best week of polling for Obama, as I noted today in both my presidential forecast update and in a look at Obama's apparent lack of a bounce from his overseas trip. However, one very important and very bright spot remains: Obama's firewall states remain untouched.
The 50%+1 Map: Obama 273--265 McCain
This is the bare bones, 50% + 1 map for Obama. It is simply the Kerry states plus Colorado, Iowa and New Mexico. And, as I noted above, Obama's advantage in these states remains untouched by current polling:
In order to win the election, McCain must win at least one of these states. However, McCain has not led in at least six consecutive polls from all of these states. In fact, Obama's lead is large enough in all of these states that there is no statistically valid way to argue that McCain is currently ahead, or even tied, in the electoral college.
This hasn't been the best week of polling. However, as long as the firewall holds, there is no need to panic. It is only when a poll shows McCain ahead in one of these six states that it will be time for real concern.