Big gaps in Romney plan on pre-existing conditions

It's harder for people switching from job-based coverage to an individual plan. They first have to exhaust a coverage option known as COBRA, which allows people with job-based insurance to keep their health plan for up to 18 months after leaving the company, provided they pay the full premium. Many can't afford that.

And there's no federal protection against being turned down for people trying to switch from one individual plan to another.

Romney could address those two gaps, making it easier for people to switch from job-based to individual coverage and among individual plans. His campaign has not specified how.

In his journal article, Romney also proposed to allow people purchasing coverage individually to deduct the cost from their income taxes, and he expressed support for purchasing pools and for allowing insurers to sell across state lines. His campaign says states will have the flexibility and resources to design programs for residents who cannot afford coverage on their own.

Individual insurance market expert Karen Pollitz, who served in the Obama administration as a consumer regulator, says the components of Romney's plan are unlikely to provide as comprehensive a guarantee as the president's Affordable Care Act.

"The ACA just says insurance companies can't discriminate against you, period," said Pollitz, now with the nonpartisan Kaiser Family Foundation. "If you've been uninsured, you can come into this market on Jan. 1, 2014, no questions asked."