Newspapers and broadcast media are always excellent sources of public opinion data. In addition, check:
GIS/Data Center (GDC)
The Rice University, Fondren Library, GIS/Data Center provides library patrons with access to GIS software and supporting hardware, to data resources, and to print and digital map resources.
The Center offers assistance and various types of instruction in using and selecting appropriate resources for the information need.
Read more about how GIS is used in the political science field.