Wrong.
I don't think I'm wrong because I recall recently reading an interview with . . . I think Gallup in which they said party affiliation is NOT a demographic because it can change at will. It is not like age or gender or income. They don't target it.
Come now, if it was targetted, then these wildly varying party mix results we see from various polls would make no sense. The polls would target the same mix over and over again. There would be no need to count how many Dems/GOP/Ind are in a given poll because it would have been arranged to be the same mix all year long.
Bump for later reading.