Partisan identification in polls

[CARLHAYDEN]

Here is a key quote from a posting by Jay Cost, about three years ago:

Gallup and Pew Consistently Underestimate Republican Identifiers Relative to the Exit Poll.

Pew tends to be more pessimistic about the GOP's standing than Gallup, but both always show fewer Republicans than the exit polls. The difference is typically 5 to 7 points.

www.realclearpolitics.com/horseraceblog/2009/05/understanding_recent_changes_I.html