(CNN) California has reversed several years of slipping sign ups on its Affordable Care Act exchange.

The key was restoring the penalty for remaining uninsured and boosting financial help to pay for coverage -- two state provisions that are new this year, said officials at the Covered California exchange.

This led to a 1.6% increase in sign ups, to 1.54 million people, on the state-run exchange for 2020. The boost was driven by a 41% jump in new customers, which offset an 8% decline in renewals.

"It's absolutely clear the penalty provided motivation to shop. So it made a big difference," said Peter Lee, Covered California's executive director. "It's also clear that the federal and state subsidies helped people buy."

immigration, auto emissions, Bolstering the Affordable Care Act has been a priority of several blue states, as well as moderate presidential candidates, after the Trump administration and Republicans in Congress moved to weaken it. Defending the landmark health reform law has also allowed Democratic governors, particularly California's Gavin Newsom, to draw contrasts between themselves and President Donald Trump. The two have tangled in recent years over abortion homelessness and presidential tax returns

Read More