President Obama said Health and Human Services Secretary Kathleen Sebelius has done “a great job” setting up Obamacare despite his extreme frustration with the massive failures of, the main portal for people signing up for the new Obamacare exchanges.

“You know, I think Kathleen Sebelius, under tremendously difficult circumstances over the last four and a half years has done a great job setting up the insurance markets so that there is a good product out there for people to get,” he told NBC's Chuck Todd in an interview Thursday at the White House.

Sebelius, he said, “doesn't write [computer] code” and “wasn't our IT person.”

The former Kansas governor, he said, would be the first to admit that “if we had to do it all over again, that there would have been a whole lot more questions that were asked, in terms of how this thing is working. But my priority right now is to get it fixed.”

Speaking in Dallas Wednesday to volunteers with Organizing for Action, a pro-Obama group that is working to enroll consumers in the health law, the president said the website woes have driven him “crazy." But during those remarks and in his interview Thursday Obama added that it's his responsibility to make sure it's up and working as soon as possible.

“Ultimately, the buck stops with me,” he said. “You know, I'm the president. This is my team. If it's not working, it's my job to get it fixed.”

The massive failure threatens to undermine the new law because the insurance exchanges depend on healthy young people to enroll in large numbers to offset sick people.

Obama said the administration's team of tech experts are working overtime to get the website functioning properly to make it far easier for applicants to enroll.

"I take responsibility for that. My team takes responsibility for that and we are working every single day, 24/7 to improve it," he said. "And it's better now than it was last week. It's certainly a lot better than it was on Oct. 1... I'm confident it will be a lot better by Nov. 30 and that the majority of people are going to be able to get on there."