Despite Republicans’ attempts to tear down the Affordable Care Act, the law’s fifth annual insurance enrollment season began Wednesday morning, opening a 45-day window in most of the country for eligible consumers to buy health plans for the coming year.

As of 7 a.m. Eastern time,, the federal website on which ACA marketplaces in 39 states rely, went from previewing insurance options to saying, “2018 Open Enrollment is here.”

Unlike the past four years, when the Obama administration marked the arrival of each sign-up period with considerable hoopla from the White House on down, President Donald Trump and his health-care advisers limited their statements about the start to a single, low-wattage tweet Tuesday afternoon from the Health and Human Services Department.

[Anthem retreats from ACA market in Maine]

The uncustomary quiet – federal health officials have slashed by 90 percent the government’s spending on advertising and other strategies to spotlight the law’s marketplaces – is one of several dynamics prompting widespread predictions that fewer Americans will end up with coverage. Sign-ups swelled during each of the marketplaces’ initial years. They dipped slightly to 12.2 million for 2017, a decrease that appears to have been caused by a slowdown during the enrollment period’s final days when Trump took office and his administration pulled much of the planned outreach campaign.

For the latest enrollment, recent surveys suggest that many Americans are confused about whether ACA insurance still is being sold and that the vast majority of uninsured people eligible for such coverage don’t know that now is the time to buy it. The law’s marketplaces provide access to insurance to people who cannot get affordable health benefits through a job. More than 8 in 10 qualify for federal subsidies to defray the cost of health plans’ premiums.

This lack of awareness is especially problematic given insurers’ continued departure from the marketplaces in parts of the country and the “unusual ways” monthly premiums are changing before subsidies are taken into account, said Karen Pollitz, a senior fellow at the Kaiser Family Foundation.

“It’s going to be very important [for people] to go onto the marketplace site and see what their situation is going to be,” she said. And with the enrollment period on cut in half from three months – Dec. 15 is now the deadline for the federal exchange – “waiting until the last minute is not a good idea. If people are used to waiting until after the holidays, they will be very disappointed,” Pollitz added. “They won’t be able to get insurance for 2018.”

Consumers who already have ACA coverage will have special trouble if they wait for the federal exchange to re-enroll them automatically. In previous years, they had several weeks to switch or drop plans after autoenrollment in mid-December. But there is no longer time available to make such changes; the renewals will be done the day after the sign-up season ends.

In the absence of a robust federal enrollment campaign, Democratic members of Congress, activists, local officials and several celebrities will be launching a major push Wednesday at events across the country.

In Nashville, Democratic Mayor Megan Barry will join Grammy Award-winning musicians Bill Lloyd, Ashley Cleveland, Gary Nicholson and Todd Sharp at a “Health Care Rocks” event. In New York City, Democratic Mayor Bill de Blasio will gather with other local officials, representatives from Planned Parenthood and others in the atrium of Harlem Hospital.

Supporters of the law will tweet with the hashtag #GetCoveredNow to spread the word that enrollment is underway, and former HHS secretary Kathleen Sebelius, who oversaw the rocky beginnings of four years ago, will do media interview to tout the importance of sign-ups.

Still, like many of her counterparts in the dozen states that run their own insurance marketplaces under the law, the head of the DC Health Benefit Exchange Authority is worrying over whether consumers will know to enroll.

In previous years, about half of its customers found their way to by first going to and being transferred once they typed in where they live. With so much less federal effort to generate attention, executive director Mila Kofman said, she is not sure that will again happen.

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