IT’S POTEMKIN VILLAGES ALL THE WAY DOWN: No, 2.1 million haven’t enrolled in Obamacare plans.

With President Obama’s health care law scheduled to begin in earnest when the new year kicks off, Secretary of Health and Human Services Kathleen Sebelius claimed on a Tuesday conference call that as of Dec. 28, “2.1 million people have enrolled in a private insurance plan” through the program.

Later in the call, Sebelius emphasized that enrollments wouldn’t be completed until individuals paid their first month’s premiums.

But HHS officials still won’t disclose how many of the 2.1 million they claim enrolled through the federal healthcare.gov website or one of the state-based exchanges actually paid for coverage.

Though Sebelius left the call before the question-and-answer session, Centers for Medicare and Medicaid Services spokeswoman Julie Bataille declined several times to provide payment information. . . .

Later in the call, CNN’s Jim Acosta asked Bataille if she could at least say with confidence that a “very high percentage” of those 2.1 million had paid.

Instead of answering in the affirmative, Bataille said, “We are confident that those consumers have selected a plan and know what the next steps are for them in terms of securing coverage.”

The Wall Street Journal reported on Tuesday that: “As of Monday, however, only about half of enrollees billed for plans offered by more than 100 insurers in 17 states had paid their first month’s premium, said Mark Waterstraat, chief strategy officer at Benaissance, a third-party billing firm that works for those insurers.”

It isn’t clear whether that figure is indicative of the story nationwide, and it’s true that insurers have opted to give individuals until at least Jan. 10 (in some cases longer) to pay their premiums for coverage beginning on Jan. 1.

But there’s no reason to believe Sebelius’s claims that 2.1 million have enrolled as of Dec. 28, and journalists shouldn’t report that 2.1 million enrolled until HHS releases data showing that 2.1 million paid for their plans.

During the call, Bataille also declined to provide a demographic breakdown of those who have selected a plan so far or say how many of the 2.1 million signing up for insurance were previously uninsured.

Demographic information is important, because it is vital for the exchanges to attract a critical mass of young and healthy enrollees to offset the costs of covering older and sicker participants in the program.

Also, because millions of Americans have received cancellation notices from insurers, analysts want to know whether the law resulted in a net gain of those who have private insurance. Knowing how many of the 2.1 million signing up were previously uninsured could help provide insight into the question.

If the numbers were good, they’d be telling us.