National polls are interesting to watch, since we can look at trends and it gives us the bigger picture. Bot we all know that the EV is what matters, but there are some problems with recent state-polls as well.
FLORIDA:
Yesterday Rasmussen released 5 "battleground" polls: CO, FL, OH, PA and VA. Most of them where close and Florida as an example was tied. So, today PPP (famous along with ARG for being wrong) released a poll from Florida where McCain increased his lead by 2 points to 50-45. But, here is the trouble they have republican as 43%, democrats at 41% and independents at 16%. Exit polls in 04 had it Republicans 41%, Democrats 37% and independents 23%. I find it hard to believe that Republicans have increased by 2 point the last 4 years? So, I looked at PPPs last poll, what did I find? Well, that time they had republicans 40%, Democrats 43% and independents 17%.
Well, I don`t know the exact number regarding party affiliation , but I know that things don`t change that dramatically in 1 month. It is not likely that it went from +3 D to +2 R. So I checked the results to see what the poll would have showed if party affiliation had stayed the same:
McCain 47 Obama 46.
The real story behind the PPP poll is that Obama actually have improved by 1 point.
I don`t know the exact numbers regarding party affiliation so it would be interesting if anyone have an idea.
VIRGINA:
Well, guess what. I did the same with SurveyUSA and Virginia, the last poll had McCain +1, todays McCain +2. Party affiliation:
First Poll: 32 R, 37 D, 25I
Second Poll: 35 R 36 D 20I
An extreme change..... Do I believe it? NO!
What would the result if affiliation had stayed the same?
45-45 (Obama ahead by 0,5)
So, the change in party affiliation again "helps" McCain.
This must be a coincidence? Lets look at Washington:
WASHINGTON
SUSA again.
Last poll had Obama+7, yesterdays Obama+4
Party affiliation first poll:
28 R 40 D 23 I
Second poll:
29 R 37 D 28 I
What would the numbers be if party affiliation had been unchanged:
47-39
Well look at that Obama +8, thats better than the last poll....
This is NOT uncommon at all and it could be that a couple of other polls favor Obama in the same way, but the main point is that it matters WHO you poll, comparing one poll with another one without the same demographics or party affiliation is not good and you should at least say that this could be the reason for the change. 3 polls and all "favor" McCain because of a visible change in party affiliation, a change that have no connection to the real world.
As I said over, I don`t know the exact number regarding party affiliation but I know that it doesn`t change that much within a month. But be careful to read the polls carefully before you get worried or excited...