Obama: Health care plan will work

• President Obama says enrollee pool is large enough to sustain health care plan
• Critics hit Obama for comment that some people need to switch doctors

President Obama said Friday that enough Americans have signed up for his health care plan to make it a success, while critics cited his comments that some people may have to "switch doctors."

In an interview with WebMD, Obama said 4.2 million people have signed up for coverage under new health care exchanges, and -- while that is below administration projects -- the pool "is already large enough that I'm confident the program will be stable."

Obama, who used the interview to encourage more sign-ups, said it is still important that enough young, healthy people sign up in order to offset the costs of older, less healthy people.

Critics of the health care plan, meanwhile, pointed to another Obama comment during the WebMD interview: "For the average person -- many folks who don't have health insurance initially -- they're going to have to make some choices. And they might end up having to switch doctors, in part because they're saving money."

In a blog post, the conservative Heritage Foundation displayed a video from 2009 in which Obama said, "no matter what you've heard, if you like your doctor and health care plan, you can keep it."

Heritage said "we knew this was coming -- because it's been happening to Americans for awhile. The president finally admitted that you can't necessarily keep your doctor under Obamacare."

Some Americans have seen insurance policies canceled because they don't meet the new standards of the law, though the administration is allowing temporary extensions of many of those policies.

On WebMD, Obama noted that some business health plans often require participants to change doctors if they change networks.