http://www.vote-smart.org/resource_political_resources.php?category=Demographics%20and%20MapsAmerican National Election Studies
http://www.electionstudies.org/...Political Geography
http://garnet.acns.fsu.edu/...Redistricting Resource Center
http://www.ncec.org/...United States Census Bureau
http://www.census.gov/Voting And Registration
http://www.census.gov/population/www/socdemo/voting.htmlMapping the Electoral Process
http://www.esri.com/industries/elections/business/demographics.htmlVoting Maps
http://www.verifiedvoting.org/verifier/===============
I don't know if this helps but it looked interesting.
http://poll.gallup.com/content/?ci=21928March 15, 2006Democratic Congressional Lead Among Registered Voters Largest Since '82 Midterm
Lead by 55% to 39% on generic ballot
by Jeffrey M. Jones
The latest CNN/USA Today/Gallup poll finds the Democratic Party leading the Republican Party
55% to 39% among registered voters in the generic congressional ballot.
This is the largest lead Democrats have held over Republicans in the 2006 campaign thus far,
and the largest lead Democrats have enjoyed among registered voters in a midterm election since 1982.
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Voters Seem Ready for a Change of Scenery in Congress
http://news.google.com/news/url?sa=t&ct=us/6-0&fp=44ae438a079e3278&ei=8p-uRPj5CZSWaLuQ8K0J&url=http%3A//poll.gallup.com/content/%3Fci%3D23509&cid=0Gallup Poll News, DC - Jun 28, 2006... the latest USA Today/Gallup poll, conducted June 23-25, 2006,
the Democrats now lead the Republicans 54% to 38% as the preferred party of registered voters in ...
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I had to add this. I just saw it.
http://poll.gallup.com/content/default.aspx?ci=23560July 05, 2006
Not Much for Either Party to Celebrate in Congressional Ratings
Independents widely critical of Republican and Democratic leadershipby Lydia Saad
Registered voters currently prefer the Democratic Party to the Republican Party
by a 16-point margin for this year's midterm congressional elections;
however, this is not necessarily a ringing endorsement of the minority party.
Other data from the same June 23-25 USA Today/Gallup survey suggest that Americans
are discouraged with both parties in Congress and may simply be looking for a change.