Software contractors who built the Patient Protection and Affordable Care Act federal exchange system defended their work at a raucous, standing-room-only House hearing convened Thursday to allow Republicans an opportunity to cast "Obamacare" in the most negative light possible.

The hearing was held to highlight the problems faced by the federal exchange. The federal exchange is mainly designed to serve the 34 states that have refused to open their own exchanges.

The federal site, however, has faced severe complaints from potential users of inability to log in, lengthy delays, incorrect information relayed to insurance companies and other problems. The administration has acknowledged it didn't anticipate the huge response to the site's launch, as well as design problems hindering access.