The Affordable Care Act's fifth enrollment season ends Friday in most states. (HealthCare.gov/HealthCare.gov)

Consumers jammed call centers and enrollment offices in the final sprint toward the Friday deadline in most of the country to get Affordable Care Act health plans for 2018, defying months of naysaying by President Trump about the law's insurance marketplaces.

In several states, enrollment helpers reported a crush of interest in recent days. Some navigator organizations, which help people sign up, received more requests for appointments than they could accommodate — a consequence of an enrollment season that is half as long as the past three years' time frame and large cuts by federal officials in grants to those groups.

"I could have really used the extra $900,000," said Jodi Ray, project director of Florida Covering Kids and Families, which received $5.8 million a year ago, more than any other organization. "We could have used the extra staff."

"You hang up from one call, and you get another," said Julia Holloway, who directs the navigator program at Affiliated Service Providers of Indiana. The state lost 82 percent of its anticipated funding, more than anywhere else. And with in-person assistance now scarce, Holloway said one of her only remaining navigators was staffing the phone line to try to resolve as many callers' questions as possible.

Since Thursday, people contacting federal call centers in the 39 states that use the HealthCare.gov website consistently got a message asking them to leave their contact information and await a call back, according to officials of the Centers for Medicare and Medicaid Services (CMS). They will be allowed to complete their insurance applications, even if they are contacted after the deadline of midnight Pacific time.

By late Friday afternoon, however, HealthCare.gov itself had not become so crowded that consumers were being diverted into online waiting rooms — as had occurred on the deadline day for ACA coverage each of the federal insurance exchange's past four years.

Navigators said the website functioned relatively smoothly this year, with sporadic and minor glitches and slowdowns — nothing like the profound defects that stymied insurance-shoppers when the law's marketplaces first opened in the fall of 2013.

This fifth year posed a test of the marketplaces' staying power, as the boosterism of the Obama administration gave way to Trump's vocal hostility and persistent efforts by a Republican Congress to dismantle many core features of the 2010 health-care law.

On the final day, CMS tweeted encouragement for Americans to sign up by the deadline. By the most recent count released by the agency, nearly 4.7 million people had signed up as of last weekend in the states using HealthCare.gov. That number did not include current ACA customers who will be automatically renewed by the government after the enrollment period or people signing up in 11 states, plus the District, that operate their own insurance exchanges.

The Senate repeatedly failed to pass ACA-repeal legislation over the summer and fall, but a big sideswipe to the law could be imminent. A compromise between the House and Senate over the biggest federal tax overhaul in decades contains a provision that in 2019 would end enforcement of the ACA's requirement that most American carry health insurance. The two chambers plan to vote on the tax agreement next week.

Debate long swirled within both political parties over whether such a mandate is necessary to reach close-to-universal health coverage, but the idea of eliminating the law's tax penalties for people who flout the requirement has become part of GOP orthodoxy. Congress's nonpartisan budget analysts estimate that doing so would lead to 13 million more uninsured Americans within a decade and drive up health plans' premiums.

The ACA marketplaces were created to make coverage more accessible for people who cannot get affordable health benefits through a job. The high point for enrollment was the 12.7 million consumer who had signed up for 2016 coverage by the end of that enrollment period.

This season, most of the state-run marketplaces will allow customers to keep signing up for health plans until late December or January.

And residents of a few states in the federal insurance exchange have a special enrollment period until Dec. 31 because their communities were damaged by hurricanes this fall. According to CMS officials, the extra time is available to people in Florida, Texas, Louisiana, South Carolina and Georgia — and others who lived in those states during the storms.

Fred Ammons, chief executive officer of the navigator organization Health Care Central Georgia, said he has been trying to play down the extension to encourage as many people as possible to enroll before the regular deadline. After Friday, he pointed out, "people will not just be able to go to HealthCare.gov and have it magically work." They will need to telephone a federal call center, although navigators can still help them decide on a plan.

The Georgia group has been functioning with 15 percent of the federal navigator grant it had last year, with a reduced cadre of paid staff and a score of volunteers. "Our remaining staff put their heart and soul in this," Ammons said. Even though the grant is intended for work year-round, "we will have some significant contraction of staff."