That variable can be controlled for, and if the sample size is big enough, it can be done and still yield valid results with an acceptable margin of error. This is what you would hope for from poll designers who have at least taken Quantitative Analysis 101.
I am not a polling expert, so I cannot comment either way. But I have worked on a farm before, and I know the smell of manure when I smell it.
Ricter is quite right regarding the statistics issue, as I'm sure you are in your above noted area of expertise. Why is it, though, that you guys always seem to get congested sinuses at around election time?
Imho, no need to be an expert. If you note that your sample of those who listened to the speech is skewed, by party affiliation, from a representative sample of the general population, you randomly subtract from the over-represented responses until your sample is again, by party affiliation, representative of the general population. Sure, the sample is going to be smaller, because many reps didn't listen to the speech, and many dems did, so you have a lot (if the sample is really skewed) to subtract. But, if the remaining sample is still large enough it will be statistically valid to the generally accepted margin of error. Now, if you compare your sample's two party's responses to each other, you may find the dems overwhelmingly approved, but what you would not then find is that the reps overwhelmingly disapproved, because if that were the case you would not have a result of 91% for and 9% against. From a "my team vs. your team" perspective, this poll's results are not encouraging or discouraging. The question was about approval for the president's ideas. Sure, most of us agree about those, he spoke vaguely about noble ideals. But, the methods to achieve those, there's the problem--the devil is in the details, and that was not part of the poll.
First of all, don't pretend to have any idea what I think or who I stand for, or to group me in with any "guys" or group of any sort. That's your first mistake. As for what occurs during election time, the topic of this thread is the CBS poll regarding the SOTU. That's it. And it is also the only thing I am commenting on. You should probably have done your usual snide remark one-liner and left it at that instead of trying to judge me.
Read the entire poll. It was not just about the ideas the President had. That was merely what CBS conveniently latched onto in their "Read all about it" headliner.
Well we all know what the real problem is.....an obstructionist, intransigent GOP who will do all they can to block any progress that could possibly be credited to Obama and the dems.