Enrollment numbers on the federal and state insurance marketplaces picked up sharply in November, but the figures still lag behind original forecasts.

The Department of Health and Human Services (HHS) reported Wednesday 364,682 Americans have selected an insurance plan on either a state or the federally-run exchange since Oct.1. Of these enrollees, 227,478 enrolled via the 16 state-based marketplaces and 137,204 via the federal marketplace Healthcare.gov, which serves 36 states.

These numbers are big improvement from November’s report of just 106,185 enrollees during the first month of open enrollment. The increased enrollment is likely due to the upgrades that have been made to Healthcare.gov, which has struggled since its’ initial rollout on Oct. 1. The administration now claims the site can now handle up to 800,000 visitors per day and 50,000 users at a time.

The report comes the same day HHS Secretary Kathleen Sebelius returned to Capitol Hill to testify before the Energy and Commerce health subcommittee where she announced an investigation into the rocky launch of Healthcare.gov.

“Healthcare.gov is working faster, responding more quickly, and we’re able to handle larger volumes of concurrent users,” Sebelius said. “Pages that once took eight seconds to load are now responding in under a second. The site’s error rate, which once topped 6% has been driven down to below 1%.”

The latest figures count everyone who has signed up for coverage as an enrollee-even if they haven’t paid their premium, which goes against the insurance industry’s standard practices.

“The jury is still out about how many of these people are truly enrolled and will stay enrolled and continue to pay their premiums,” says Devon Herrick, National Center for Policy Analysis senior analyst. “The report never actually mentions who many people have paid their premium.”

Brookings Institute visiting fellow Larry Kocot says that while the numbers are looking better, the administration still has a long way to go to reach its projected enrollment goals.

“We still don’t know how many of these applications will result in actual enrollment with a premium paid by the enrollee,” Kocot says. “Also, there will invariably be problems with initial on-boarding of enrollees on and after Jan. 1, so there is still a lot of work to be done.’”

Under the ACA, individuals must have health insurance by the end of open enrollment period on April 1, 2014, or they will face a penalty of $95 or 1% of their annual income for failing to comply. Those who want their insurance to kick in on Jan. 1, they must enroll in a plan by Dec. 23.

Nearly six million people have received cancellation letters that their policies would be terminated at the start of the year because they don’t’ meet ACA standards. The president’s signature legislation mandates all policies include 10  essential health benefits, including maternity care to ambulatory services and prescription drug benefits.

The administration had projected in September to have 3.3 million enrollees by the end of December, meaning they would need 2.9 million enrollees by the end of the month.  In year one of the ACA, the administration has projected it would enroll 7 million people—2.7 of which are young and healthy people needed to keep premium costs down for the older and less healthy population of enrollees.

Yevgeniy Feyman, Manhattan Institute scholar, says there is no way the administration will meet its goals, even with the recent surge.

“They are way off their goal—it's not realistic to have 3.3 million people enrolled foe 2013 with just days left until the Dec. 23 deadline,” he says. 

The report also fails to detail enrollees by age, says Feyman, and the pool of policyholders is key to making this law succeed. A recent poll from the Harvard Institute of Politics finds young people without insurance are “unlikely to enroll” with less than one-third saying they would sign up for coverage.

“Age distribution matters a lot too,” he says. “If these enrollees are skewed toward the older crowd, that will not be a good thing come January 1.”

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