With just a few days left in the signup period for consumers purchasing health insurance through the government's Healthcare.gov platform, enrollment numbers continue to lag behind last year.

In the past week, 1,005,673 people enrolled in a health insurance plan, bringing this year's running total up to 3,882,671–approximately 250,000 less than the same time last year.

Those numbers are expected to benefit from the usual last-minute surge in signups, as well as the carryover of millions of Americans who purchased a plan in 2019 and will be auto-enrolled in a new plan for 2020.

Related: Number of participating ACA insurers increases for 2020

Additionally, the numbers do not include signups in states operating their own exchanges, many of which have different enrollment deadlines.

Still, ACA enrollment has faced a number of headwinds, not the least of which is the ongoing legal challenge against its constitutionality in the absence of an individual mandate penalty. In addition, funding for marketing and outreach has been cut significantly in the last few years.

Read more: 

• New 'super broker' system cuts HealthCare.gov out of the ACA signup process
• 6 states move to set up their own ACA marketplaces
• More than half of American families could feel the impact if the ACA is overturned