People looking for health insurance in the grip of the omicron surge have through Saturday to sign up for taxpayer-subsidized private coverage under the Obama-era Affordable Care Act.

President Joe Biden's administration is on track is to deliver robust enrollment numbers, but those gains could turn into a mirage if congressional Democrats remain stymied on Biden's social agenda package. Biden's coronavirus relief bill has been providing generous subsidy increases that benefit new and returning customers. The juiced-up assistance will go away at the end of this year without further congressional action.

"The determining factor in whether this is a lasting gain in enrollment is whether the subsidies are extended," said Cynthia Cox, who follows health insurance trends at the nonpartisan Kaiser Family Foundation. "The biggest threat to enrollment would be if these subsidies expires." Millions of people could see their monthly premiums double and deductibles would also shoot up.

Health and Human Services Secretary Xavier Becerra said Thursday that about 14.1 million people have enrolled or renewed coverage as of Jan. 8. That's a gain of roughly 2 million covered through HealthCare.gov and state-run insurance marketplaces. Two GOP-led states — Florida and Texas — are seeing particularly strong sign-ups.

"Dependable health care coverage is in reach at affordable rates," said Chiquita Brooks-LaSure, head of the Centers for Medicare and Medicaid Services, which runs the program. Because of the Obama health law, or ACA, people cannot be turned down for coverage due to medical problems.

In addition to improved subsidies, the Biden administration has also focused more energy on outreach, increasing the number of enrollment counselors and stepping up advertising.

"It's mostly good news for the administration," said Cox.

About 9 in 10 U.S. residents currently have health insurance through a mix of employer, public and individual plans, but 28 million people remain uninsured even with the COVID-19 pandemic in its third year. Most uninsured people would be eligible for taxpayer-subsidized coverage, and surveys show many are just not aware of that.

People who sign up by Saturday will have coverage effective Feb. 1.

After Jan. 15, people still looking for coverage will need a specific reason, such as losing a job or a change in family circumstances, to qualify for a special enrollment period.

Federal officials recommend that deadline day procrastinators enroll by midnight local time in their community.