I generally don't regard Alexa to be a reliable source of traffic data for local websites due to sampling methodology and size issues, but when applied to the presidential race, it may provide a fairly accurate indication of enthusiasm about the candidates. Here's a snapshot of the last month's traffic for the Obama, Clinton and McCain campaign websites. It certainly doesn't look good for Clinton.

You can see the live data at Alexa.com.
[Update: I had generated a graph for hilaryclinton.com, which apparently is owned by a domain squatter, not the correct hillaryclinton.com domain. I've fixed that and the Clinton line is somewhat higher, but still badly behind Obama.]
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