The bipartisan Pew Research Center has done a rather extensive survey on what Americans think about their government and politics. It's excellent, and I urge you to go read the entire article.
The results shown in the charts are from surveys Pew did between August 27th and October 4th of this year. They questioned a random sample of 6,004 adults, and the survey has a margin of error of 1.5 points.
Here are some of the charts I found interesting: