Now that's a West Coast offense.
California's Obamacare insurance exchange enrolled more than 53,000 people in health-care plans in just the first three days of this week, a blistering pace that had officials crowing on Thursday.
"December is turning out to be an enormous month," said Peter Lee, head of the Covered California exchange.
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Lee said the surprisingly strong level of enrollments—which comes just days before the key Dec. 23 enrollment deadline—puts the state on track to beat its original projection of signing up as many as 700,000 people in Obamacare insurance by the end of open enrollment in March.
From Oct. 1 until Nov. 30, a total of 109,296 people enrolled in private Obamacare plans sold on Covered California's website.
"We could easily exceed those projections," Lee said. "But we aren't done."
Lee encouraged people to sign up online to get enrolled in health plans by Dec. 23, the deadline for enrolling in coverage that begins Jan. 1.
He noted that Covered California's enrollment of 53,510 people in the first three days of the week is significantly higher than the 31,000 who enrolled in the whole month of October.
Lee said 13,653 people signed up on Monday, which jumped to 19,351 on Tuesday, and 20,506 people on Wednesday.
"Twenty thousand in one day is a lot," Lee said. "I think that's going to be greatly exceeded on the 21st. By how much, I don't know."
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"The enrollment we're seeing is remarkable by any account," Lee said. "It is a very strong testament to Californians both learning about the Affordable Care Act and taking advantage of its benefits."
Lee vowed that people who begin applications online by next Monday, but are unable to complete them "because of a problem on our end ... we're going to get them through" and have them enrolled in heath coverage effective Jan. 1.
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California is one of just 14 states operating its own online marketplace to sell insurance for the Affordable Care Act. HealthCare.gov, the federally run site, is selling Obamacare insurance in the remaining states.
The Golden State has been credited for largely avoiding the technical glitches that plagued HealthCare.gov and a number of other state-run Obamacare exchanges in the first month of the rollout of ACA insurance sales.
—By CNBC's Dan Mangan. Follow him on Twitter @_DanMangan