(Bloomberg) -- Obamacare-loving California led the nation in embracing thehealth-care law, and in enrolling its citizens for 2014coverage.

This year, however, sign-ups for private health plans inCalifornia, New York and other states that opted to build and runtheir own insurance markets has stagnated. Yet in more conservativeparts of the country that declined to participate and whereenrollment is run by the federal government, sign-ups have surged.

That includes Florida, where Governor Rick Scott opposes thelaw. After a 2012 Supreme Court decision affirming it, Scott saidthat “the entire act should have been held invalid.” For 2015, 1.6million Floridians chose insurance plans sold through the federalhealthcare.gov system, 62 percent more than a year before,according to an analysis by Charles Gaba, a blogger in BloomfieldHills, Michigan, who has accurately predicted enrollment under thelaw.

The development is made stranger because California had moreuninsured people than any other state in 2013,the year before the health law’s insurance expansions began -- 5.8million, according to the Kaiser Family Foundation, a healthresearch group. About 3.6 million people were uninsured inFlorida.

New York, which like California runs its own enrollment system,saw modest growth with about 407,000 enrolled, 37,000 more than ayear ago, in a state with 1.8 million uninsured people. InCalifornia, enrollment was flat, with about 1.4 million signed up-- the same as in 2014.

In the 37 states that used the U.S.-run website, growth insign-ups from 2014 to 2015 ranged from 25 percent to 81 percent,according to Gaba. Among states that run their own exchanges, onlyMassachusetts and Hawaii did better -- in part because those twostates struggled with technology failures in 2014.

Medicaid may be one reason why. Any comparison of enrollment inCalifornia and Florida should include people in the program forlow-income people, said Dana Howard, a spokesman for CoveredCalifornia, the state’s Obamacare agency.

California and New York both expanded Medicaid to cover theworking poor in 2014. Florida, Georgia, North Carolina and 19 otherstates didn’t, and as a result some low-income adults in thoseplaces who would have been eligible for Medicaid are insteadenrolled in private coverage. California’s uninsured population hasbeen halved since last year, including its Medicaid expansion,Howard said.

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