Katie Thomas

Millions of people could qualify for federal subsidies that will pay the entire monthly cost of some health care plans being offered in the online marketplaces set up under President Barack Obama's health care law, a surprising figure that has not gotten much attention, in part because the zero-premium plans come with serious trade-offs.

As technical failures bedevil the rollout of President Barack Obama's health care law, evidence is emerging that one of the program's loftiest goals -- to encourage competition among insurers in an effort to keep costs low -- is falling short for many rural Americans.