healthcare.gov itself was a Ruby Jekyll static site. It was on GitHub[0] for a while, but mysteriously disappeared. Here[1] is a clone of it, and what seems to be the currently agreed upon canonical version.

My state appears to be using Joomla based on the meta-generator tag in it's head tag. http://www.avenueh.com/

[0] https://github.com/CMSgov/HealthCare.gov-Open-Source-Release

[1] https://github.com/blencorp/HealthCare.gov-Open-Source-Relea...