More importantly, the majority of the citizens of the US would prefer if current controversial issues were resolved in compromise. For example, a large portion of Americans believe that abortion for convenience is wrong, and that late-term abortion when health is not of issue is wrong. But most also believe that there are many very valid situations for abortion (nearly all would support abortion in the case of rape, or if the health of the mother was in danger, for example).
But politicians and whatnot draw lines: are you pro-choice or pro-life? There is no middle ground in the political picture, it seems.
And if you look at the results in this thread, I think that this makes sense. The majority of respondents came forward with results in the 60%-70% liberal range, which could well be considered moderate.