ONE OF THE BIGGEST questions hanging over the health-care system is how many young Americans will sign up for coverage once the Affordable Care Act begins to phase in this October. If too few buy insurance on the markets that the government is creating, insurance companies would be stuck covering primarily the the old and the sick. They would have to pay out more per customer. Their customers, in turn, would have to pay more to those companies for coverage. The stakes for the Health and Human Services Department, which is overseeing the transition, are tremendous.

But they are not high enough to justify HHS Secretary Kathleen Sebelius dancing around serious ethical lines.

The department admitted recently that Ms. Sebelius has solicited private support — including from insurance companies — for Enroll America, a nonprofit group devoted to expanding access that a former Obama administration staffer runs.

HHS argues that there is no problem here. Ms. Sebelius didn’t ask companies in the health-care industry for money, but other sorts of support for Enroll America’s efforts.

Besides, the department also says, the secretary would have been well within the law to do both; a 1976 statute specifically allows the government to encourage others to support groups that promote public health.

So far, HHS says it has asked only two entities to donate money — the nonprofit Robert Wood Johnson Foundation and tax firm H&R Block — and neither company is regulated by the agency.

But Sen. Lamar Alexander (R-Tenn.) says that Ms. Sebelius has violated the principle that Congress is the body empowered to establish funding levels for the government’s activities and that no administration can short-circuit that process by soliciting and directing donations for things it deems important. In a letter to Ms. Sebelius, he argues that her actions “may violate federal appropriations laws,” and he demands information on how much HHS has coordinated with Enroll America.

The legal question is still murky. The ethical one is less so. The Post’s Sarah Kliff, who broke the story, reports that at least one official in the health-care industry feltpressure to give money and other forms of support to Enroll America. Given that HHS directly controls the markets in which the insurers operate, we would hardly blame them for reading a lot, even too much, into the secretary’s requests and feeling nervous about them. But even if they didn’t, it would have been easy to expect donations to curry favor with Ms. Sebelius.

When we hear that Congress hasn’t given HHS the money it needs to implement the Affordable Care Act, we sympathize. When we see a cabinet secretary leaving herself open to accusations of impropriety, we can’t.