The Gallup Poll each year asks Americans to self-identify their political philosophy. The 2011 results are available (http://www.gallup.com/), with 41% self-identifying as conservative, 36% moderate, and 21% liberal. These results confirm that the nation tilts center-right but can easily move center-left.
These numbers also show why Republican and Democratic parties get into electoral trouble when they cater to their ideological base and make moderates uncomfortable.
There are also interesting differences among the political philosophies of Republicans, Democrats, and Independents.
The Republican party is 72% conservative, 24% moderate, and 4% liberal. The Rockefeller wing has just about died out, with now moderates often derisively called Republicans In Name Only or RINO by the ascendant conservatives that control the Republican party.
The Democratic Party's biggest block is moderate voters at 39%, with liberals at 38%, and conservatives at a far from inconsequential 22%. The Democratic Party is much more ideologically diverse or fractious than the much more cohesive Republican Party.
The fastest growing category of voter is Independent. The biggest block of Independent voters are moderate voters at 44%, with conservatives next at 35%, and liberals at 20%.
No matter ones political philosophy, I would urge that citizens put facts at the center of understanding what works and what makes sense. Doing so requires more effort, even work, as fact-centered thinking contradicts the ideological shortcut to knowing what is "right." Moderates embrace fact-centered thinking more readily than highly ideological voters of the right and left. But fact-centered thinking is good for all political persuasions.