President Obama personally apologized to the American public on Thursday, saying he is sorry that millions are losing their insurance coverage even though he promised people could keep their existing health plans if they liked them under Obamacare.

“I am sorry that they are finding themselves in this situation based on assurances they got from me,” he told NBC News' Chuck Todd in an interview at the White House.

“We've got to work hard to make sure that they know we hear them and we are going to do everything we can to deal with folks who find themselves in a tough position as a consequence of this,” Obama added.

Ultimately, the president said he would be judged on whether more Americans were helped from the bill than before it became law.

"I hope people are going to look back and say we have better protections than we had before," he said.

Reacting to the apology, Republicans said it rang hollow, and pointed out that the president didn't immediately issue it right away in the interview. Senate Minority Leader Mitch McConnell, R-Ky., went as far as to say the mea culpa sounded "half-hearted."

If the president is truly sorry for breaking his promises to the American people, he'll do more than just issue a half-hearted apology on TV," McConnell said in a statement.

"A great place to start," McConnell said, would be to support a bill sponsored by Sen. Ron Johnson, R-Wis., that he said would "allow Americans to do what the president promised in the first place: keep the plan they have and like."

Over the last two weeks insurers have sent out cancellation notices terminating plans that didn't comply with Obamacare's requirements, undermining Obama's promise, which he repeatedly made throughout the legislative push for the law and then later on the campaign trail.

NBC News reporter Lisa Myers reported last week that the administration has known since the summer of 2010 that millions of Americans would lose their insurance under the law.

After that report, the White House forcefully pushed back at suggestions that the president misled Americans and blamed “bad apple” insurers for altering their plans after the law passed. Because they changed their plans, they violated a provision that would have allowed those polices to be grandfathered in and retained under Obamacare.

Yet, on Monday Obama amended his previous promise to reflect the reality that millions of Americans who do not have insurance through their employers but bought it as individuals were getting thrown off their plans.

“If you had one of these plans before the Affordable Care Act came into law, and you really liked that plan, what we said was you can keep it if it hasn't changed since the law passed,” he said.

White House spokesman Jay Carney said those insurance plans fell below the new standards Obamacare set and said those being forced to find new ones would receive far better coverage through the health care law.

“What we're talking about here is the five percent in the country who currently purchase insurance on the individual market,” Carney said last month. “And that market has been like the Wild West. It has been under-regulated, it is the place where Americans have most keenly felt the challenges posed by the insurance system in this country.”

The controversy over the dropped plans and continued problems with the website threaten to undermine Obama’s signature domestic achievement.

Republican New Jersey Gov. Chris Christie on Tuesday called on Obama to own up to his mistakes and admit he shouldn't have made the “if you like it, you can keep it” promise.

“Don't be so cute,” Christie said. “And when you make a mistake, admit it. Listen, if he was mistaken in 2009, 2010 on his understanding of how the law would operate, then just admit it to people.

“Say, 'You know what? I said it, I was wrong. I'm sorry and we're going to try to fix this and make it better.' I think people would give any leader in that circumstance a lot of credit for just, you know, owning up to it.”