Can you describe how you set Akamai to host the site? I'm familiar with using S3 to host a static site, and using a CDN to host assets, but it's not clear to me how a CDN can be set to host a full static site. Did contribute.barackobama.com just mirror something like contribute-s3.barackobama.com?
Our Devops team configured Akamai so they would have specifics for you (@scottvdp).
With most CDNs you have what's called a pull zone that points to your origin server on a different domain. So when the user requests something like cdndomain.com/whateverpage the CDN looks for the file at pullzonedomain.com/whateverpage and then it serves what it gets back from the pull zone.
Akamai has more advanced configuration options than Amazon Cloudfront. One example of this is that our payment processors did not actually live on contribute.barackobama.com, only the static files did. So we used Akamai to setup a reverse proxy to POST the donations to a different domain. Without this reverse proxy it wouldn't have been possible because the same origin policy forbids cross domain, client-side POST requests.
In regards to Akamai and not Cloudfront - Akamai had a different offering than cloudfront. JdotP mentioned in this thread that we used Akamai GTM, it allowed us to do a lot of fun failover management which cloudfront didn't offer. It also allowed for SSL.
And why Akamai and not Amazon Cloudfront?