Ask HN: Best way to handle a temp month of large traffic spikes and requests?

Does anyone have any good articles or suggestions on how to handle a temporary spike in traffic/requests?

A friend and I, every year, run a month long contest site that's a parody of the March Madness tournament. The contest usually gets very high amounts of traffic in that month, and in the past, it tends to make the site go down quite a bit. Last year, we tried using CloudFlare (http://www.cloudflare.com), but it still seemed to go down quite a bit because people are making requests on the site (they vote). More or less, my current host just can't handle that much traffic/requests (even with the CloudFlare layer in between).

What's a good way to setup the temporary site so it has a very good up-time? Is there certain hosts? We don't make much money, so low cost is also key, as it usually is.

Any help would be amazing!