The sign-up rate for Obamacare health insurance might be dropping off steeply in February, as it becomes clear that total enrollment to date is likely 20 percent or so less than the 3.3 million touted by federal officials this week.
"I'm hearing the enrollment in February is falling off significantly," said consultant Robert Laszewski, president of Health Policy and Strategy Associates in Washington, who is in close contact with major insurance companies.
While cautioning that it was still too early this month to make predictions for what total Obamacare enrollment for February will end up being, Laszewski said, "anecdotally, the trend is probably running at 50 percent of what we had in January."
The Obama administration said Wednesday that nearly 1.15 million people had selected Obamacare plans from government-run health exchanges in the month of January, bringing to total sign-ups as of Feb. 1 to 3.3 million.
Laszewski said that if February's trend continues—and if the relatively high rate of people not paying for the plans they chose continues—he doesn't expect there is much hope for the administration to meet a revised goal of hitting 6 million people enrolled by the close of open-enrollment on March 31.
"I don't see the momentum there right now," Laszewski said. He noted that an estimated two-thirds of enrollees through January were people who previously had insurance, and who presumably were buying Obamacare plans to replace the ones they had lost because they were no longer compliant with Affordable Care Act minimum standards.
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There will be a smaller pool of such buyers, he said, because many of those people were hoping to ensure they obtained coverage by January, to prevent a lapse in coverage.
Unpaid policies chip at enrollment
Laszewski and other health-insurance industry observers said they expect that nationwide about 20 percent of people who have selected Obamacare plans did not make their first month's premium payment, leaving them without insurance. Larger, publicly traded insurers told Laszewski that they are seeing rates approaching 30 percent unpaid, while smaller, newer insurers are seeing lower rates of around 15 percent, he said.
The number of unpaid policies is chipping away at the number of people actually enrolled. For example, if the 20 percent estimate for unpaid policies is correct, that means that total Obamacare enrollment by Feb. 1 is closer to 2.6 million than to 3.3 million.
"There is a lot of industry concern about how many people will actually pay," said Michael Mahoney, senior marketing vice president at Web-based insurance broker GoHealthInsurance. He said the best rate of payments by Obamacare sign-ups that he's aware of is "in the 90s," while the worst rate is so low, "I'd rather not say. ... It's really bad."
The companies with the highest rates of paid customers are ones who aggressively follow up with enrollees via email, phone calls, mailings and text messages to get them to make that initial month's payment, he said.
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Among those not paying, the reasons range from an "unwillingness to pay" to "inability to pay," he said.
Some customers who believe they can afford Obamacare plans because they are receiving tax subsidies to offset their premium costs are surprised when they realize their plans come with relatively high deductibles, which they will have to pay in many scenarios, Mahoney said. When that happens, many decide not to pay the premium, he said.
For others, there is a lack of education about insurance and how to pay for it. Some mistakenly believe that their premium payments aren't due until next year, or will be deducted from their taxes or paychecks, Mahoney said.
The check isn't in the mail
"There's a high proportion of people saying, 'I'm just waiting for it to be taken out of my paycheck,' " he said. And even though they would be paying the same amount by credit card, or check, or monthly account draws, Mahoney said, the fact that those people have to go to the effort of making that happen is enough to cause some of them to not follow through.
Paul Hamburger, a lawyer who is co-chair of the employee benefits practice at the law firm Proskauer, said he's not surprised "at all" by how many people have ended up failing to pay for the Obamacare plans they selected.
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He said some people may have enrolled in Obamacare exchange plans only to find and buy insurance elsewhere.
Other people who selected plans "get the bills mailed to them ... [and] they didn't think it was going to cost as much as it did," Hamburger said. "Or, they didn't get the bill."
Then, there's the lack of a cancel button. The website for HealthCare.gov, the federal Obamacare exchange selling policies to residents of 36 states, still does not give customers the ability to remove their unwanted enrollment from the system, Laszewski said. And that could be inflating enrollment tallies, he said.
—By CNBC's Dan Mangan. Follow him on Twitter @_DanMangan.