Apologies for this poorly cobbled-together graph, but what it shows is interesting (even if it’s not immediately obvious).
Allow me to deobfuscate:
What you’re seeing is based on exit polls. It shows the correlation between income and vote choice. Bush and Kerry, in this case. (Who, bowing to recent “tradition,” are red and blue, respectively.)
The percentages essentially translate into the fraction of people in their income group voting for whatever party. So where Bush receives a 63% for the $200,000-and-over people, it means that 63% of those people voted for him. (I’m pointing this out because I’m not sure how readily apparent this convention is.)
The connection isn’t linear, but it’s fairly, surprisingly, straightforward. People with higher incomes voted overwhelmingly for G. Bush, and people with lower incomes voted overwhelmingly for J. Kerry.
Also interesting—though not pictured on this graph—is that the only income levels where Ralph Nader pulled any percentage points were $100-150,000 and the $200,000-and-over group.
Just thought I’d share.
(Also, please note that the Y axis does not go from 0 to 100%. While this does in fact accentuate the trends [or what-have-you], it was done mostly to save space.)