More than 1 million people chose Obamacare plans in the first two weeks of open enrollment, even as a new Republican-led federal government is threatening to repeal the program next year.

The signups on healthcare.gov, used by residents in 38 states and the District of Columbia, include about 250,000 new customers and more than 750,000 renewing their coverage, according to the Centers for Medicare and Medicaid Services.