You've probably seen some version of this data in numerical form. But it's still eye-popping in a graph ...

The graph on the left charts party identification over the last six years. Democrats held steady, then surged in the 2008 campaign and finally came down off those highs after the election. Republicans have been steadily down -- from just under 1/3 or the electorate in 2004 to just under a quarter now.

The graph to the right shows just this year. The lines look fairly similar -- but much less so when you see them in the context of the larger trend. That is, the Dems were coming off an extremely high 39% party affiliation and a build up into the election. For Republicans it's just a continuation of the same 5 year trend.

Just as noticeable -- independent affiliation is the biggest 'winner'. But for the moment at least, actual elections are zero sum games between the two major political parties. The Democratic 'brand' (we've got to understanding the world in something beside marketing terms) is holding up nicely. The GOP brand remains in steep decline.