About 500,000 Californians signed up for health coverage through the exchange as of Dec. 31.
Twenty-five percent of enrollees were between the ages of 18 and 34. Officials said more of these so-called "young invincibles" need to sign up to make Obamacare financially viable.
Covered California executive director Peter Lee said the exchange is on top of it.
"We’re bolstering our efforts to reach young people, including those that are coming in this month to register for community colleges, state colleges, universities across the state," Lee explained.
This week, Covered California is taking part in a six-hour live event on YouTube, called “Tell a Friend, Get Covered.” Lee said social media is the way to go.
"We believe, as we go forward, one of the major things we’re gonna see building on the enrollment we’ve already had, is friends telling friends," Lee said. "And in particular young people, they live and breathe social media. We are deeply in that environment, and encouraging the spreading of that message."
Nearly 9 out of 10 Californians who’ve signed up through the exchange have received a federal subsidy. Individuals who make less than $46,000 a year are eligible.
Listen online at Covered California Targets 'Young Invincibles.'