Mary Altaffer/AP

Mitt Romney said Sunday he doesn't want to get rid of all of " Obamacare," a statement that at first seemed to indicate he'd softened his position on President Obama's health care law.

"Well, I'm not getting rid of all of health care reform," Romney said on NBC's "Meet the Press." "Of course, there are a number of things that I like in health care reform that I'm going to put in place. One is to make sure that those with pre-existing conditions can get coverage. Two is to assure that the marketplace allows for individuals to have policies that cover their family up to whatever age they might like. I also want individuals to be able to buy insurance, health insurance, on their own as opposed to only being able to get it on a tax advantage basis through their company."

But the Romney campaign later confirmed that the GOP candidate had not changed his position on coverage for pre-existing conditions. Insurance companies have covered people with pre-existing conditions as long as they had continuous health care coverage.

The Affordable Care Act, on the other hand, created special health care plans in 2010 for people who have pre-existing conditions, and by 2014 it will prohibit insurance companies from denying coverage to anyone because of a pre-existing condition.

It is not a small population who would be cut from health care coverage under a proposal similar to what Romney has suggested. A Health and Human Services report published in January 2011 estimated that between 50 million and 129 million people currently have a pre-existing condition in the eyes of insurance companies. Twenty-five million of those do not have health insurance, according to the report. That number does not take into account those who have had gaps in coverage, suggesting a much larger number of people have pre-existing conditions but have not had continuous coverage.

Those gaps would be important under Romney. Earlier this year, Romney suggested that people with pre-existing conditions who didn't already have health insurance shouldn't get any special treatment.

"If they are 45 years old, and they show up and say, 'I want insurance because I have heart disease,' it's like, 'Hey guys. We can't play the game like that,'" Romney told Jay Leno during a March appearance on the "Tonight Show." "You've got to get insurance when you are well, and then if you get ill, you are going to be covered.

"People who have been continuously insured, let's say someone's had a job for a while and been insured, then they get real sick and they happen to lose a job, or change jobs, they find, 'Gosh, I got a pre-existing condition. I can't get insured,' I'd say no, no, no. People with pre-existing conditions, as long as they have been insured before, they are going to be able to continue to have insurance," he said.

On the day the U.S. Supreme Court narrowly upheld the constitutionality of the Affordable Care Act, Romney said his plan would let people with pre-existing conditions "know they will be able to be insured and will not lose their insurance," but he did not address what happens to those who have pre-existing conditions but no health insurance.

His campaign has not been more specific about Romney's health care plan, nor does his website go into detail.

The website lists as one of his priorities: "Prevent discrimination against individuals with pre-existing conditions who maintain continuous coverage."

Continuous coverage generally means having nonstop coverage. Gaps of no more than 63 days can be allowed when changing insurance companies.

But as the Washington Post pointed out, people who have health insurance and a pre-existing condition are largely protected by the Health Insurance Portability and Accountability Act, or HIPPA, which was enacted in 1996, and limits how employer-sponsored plans can deny coverage because of pre-existing conditions, and how far back they can search for them.

Read more about pre-existing conditions and HIPPA at the Department of Labor's website.

"Under current laws there are strong protections on pre-existing conditions if you're going into a group plan," said Karen Pollitz, a senior fellow at the nonpartisan Kaiser Family Foundation. "There are some protections on pre-existing conditions if you're going onto the individual market," she said.

Many group health insurers have stopped denying coverage because of pre-existing conditions altogether rather than parse through HIPPA's requirements. And for people without group or employer-sponsored coverage, many states have high-risk pools that provide insurance to those with pre-existing conditions. But the cost is often prohibitive.

The Affordable Care Act created a new $5 billion high-risk pool that has provided insurance. It has covered 77,000 people, still a small fraction of the uninsured who have pre-existing conditions.

The full ban on denying coverage to people with pre-existing conditions goes into effect in 2014, along with controls on how much more insurance companies can charge those who have pre-existing conditions.

But some people look at that generally low enrollment in the state and federal high-risk pools and wonder if the number of uninsured with pre-existing conditions is as large as 25 million.

It's like saying everyone who lives on the Gulf Coast is at risk of dying whenever there is a hurricane, said Ed Haislmaier, a senior research fellow in health policy at the conservative Heritage Foundation.

Read his argument here.

Haislmaier does not know what, specifically, Romney would suggest to fix the problem of uninsured people with pre-existing conditions.

But Haislmaier has written extensively on the subject, and said the best way to do it would be to extend the HIPPA protections to the rest of the insurance market, which he said have worked for people in employer-sponsored health insurance plans.

The flaw was that Congress didn't extend those HIPPA protections to the individual market, Haislmaier believes. "That's what the conservative solution would be," he said. "Some reasonable changes to the rules, which are essentially finishing what was left undone when you fixed 90 percent."

ABC's Emily Friedman contributed to this report.