[Most of this article is beyond stale. But I liked this one line, which essentially answers the question in his title]
http://www.nytimes.com/2011/07/31/opinion/sunday/tuning-out-the-democrats.html
The New York Times
July 30, 2011
Why Voters Tune Out Democrats
By STANLEY B. GREENBERG
<snip>
In analyzing these polls in the United States, I see clearly that
voters feel ever more estranged from government -- and that they
associate Democrats with government. If Democrats are going to be
encumbered by that link, they need to change voters' feelings about
government.
<end excerpt>
Michael