WASHINGTON (NBC) - The President reportedly knew months ago the site could have major problems, but now promises to make this end of the month deadline. "By the end of this month, it will be functioning for the majority of people who are using it," said President Barack Obama.

But 30% of Healthcare.gov hasn't even been built yet, a top health tech officer revealed in hearings Tuesday. "That 30 percent represents the payment aspect and the accounting aspects of making payments in the market place," said CMS Deputy Chief Information Officer Henry Chao.

Democrats insist the website failure is just a bump in the road. "The technology is not working, but it will, but the policy is very sound," said Rep. Nancy Pelosi, (D) California.  

But critics are now focusing on a Washington Post report that a private company warned of problems last spring, and many in the White House - including the President knew about it. "He ought to go and fire every single one of those people right now and hold them accountable," said Rep. Steve Scalise, (R) Louisiana.  

"Nobody anticipated the size and scope of the problems we experienced once the site was launched," said White House Press Secretary Jay Carney.

Now, outside experts tell congress security flaws on the site put personal information at risk.

The government says it has fixed about two thirds of the bugs that were causing the site to crash or slow down.