WASHINGTON — ObamaCare seems to be holding its own. The administration said Wednesday that 6.4 million people have enrolled for subsidized private coverage through HealthCare.gov, ahead of last year’s pace.

Despite rising premiums, dwindling insurers, and the Republican vow to repeal President Barack Obama’s health care law, about 400,000 more people signed up through Monday than for a comparable period in 2015, the Department of Health and Human Services Department said.

“Today’s enrollment numbers confirm that doomsday predictions about the marketplace are not bearing out,” said Health and Human Services Secretary Sylvia Burwell.

It’s unclear if the administration will meet its target of 13.8 million sign-ups.

That’s partly because the share of new customers is down when compared with current consumers re-upping for another year. New customers are 32 percent of the total this year versus 40 percent last year. Administration officials said they’re going to focus on getting more new customers between now and the end of open enrollment Jan. 31.

“There are zero signs that the ACA’s marketplaces are in danger of imminent collapse,” said Larry Levitt of the nonpartisan Kaiser Family Foundation, who has followed the health care law from its inception.

That carries an implicit warning for congressional Republicans, who have promised to move quickly to repeal the law. That repeal would be followed by a GOP-inspired replacement, but the whole process could take several years and it’s unclear what would happen to people with coverage in the meantime.