Plagued by robocalls offering health insurance? You're not alone.

The calls kept coming, one after the other, offering health insurance that Alex Boeger said he didn't need. Tired of the interruptions, the Houston-area marketing and Web design expert at one point tried to take matters into his own hands, ringing back the robocallers to get them to stop bothering him and his family - but the calls continued.

"I get blown up all the time," he said.

So have many others around the country: A suspicious campaign bombarded Americans with an estimated 288 million robocalls pitching health insurance in October, according to the call-blocking smartphone app YouMail, contributing to the record 5.7 billion robocalls made nationwide last month. To experts, the barrage illustrates the country's continued struggle - and its need for new legal tools - to stop a digital scourge occurring in plain sight.

Few things unite Americans in universal disgust quite like robocalls, a tactic of mass outreach that can take many forms - from legitimate reminders to pay one's bills to scams that mimic local numbers in a bid to swindle those who pick up the phone.

But the spike in health-insurance-related robocalls, which coincided with the annual fall period when people choose their coverage, highlights the complexities. While the calls may be offering perfectly legitimate services, they also appeared to come from a single originator that cycled through a series of names, such as "Executive Health" and "Whitestone Health," according to people tracking the campaign, delivering a prerecorded pitch using the same male voice.

Boeger and others bothered by the calls said they never consented to receiving them, raising the possibility that the calls violate federal law.

To stop such onslaughts, telecom giants such as AT&T and Verizon this year have started implementing anti-robocall technology that can help people spot fake numbers in real time. Regulators in Washington also have stepped up their efforts: Lawmakers on Capitol Hill are set to unveil a new, bipartisan bill that will empower law enforcement to get even tougher on the worst offenders, according to a copy obtained by The Washington Post.

But those long-sought improvements can't come fast enough, experts say, pointing to the fact that robocallers have become more sophisticated - and pervasive - even in the face of heightened vigilance by government and industry.

"They're not going to go away if we don't pass the bill," said Rep. Frank Pallone Jr., D-N.J., one of the authors of new legislation.

The act of automated dialing isn't illegal. But decades-old federal law generally requires those that ring consumers with prerecorded messages en masse to first obtain the consent of those called. Callers must also give people the ability to withdraw such consent later.

Scammers, of course, aren't inclined to follow the rules or adhere to other restrictions, such as the federal "Do Not Call" list, which is supposed to protect people from receiving unwanted telemarketing messages. And some criminals have continued to devise new ways to outsmart telecom companies, contributing to the uptick in robocalls placed to consumers last month.

"As more and more people discover how easy it is," said Alex Quilici, the chief executive of YouMail, "you've got a bigger and bigger problem."

But finding and penalizing the worst robocall offenders has been a major challenge for the two agencies that oversee the issue - the Federal Communications Commission and the Federal Trade Commission. The agencies have secured record fines against those that call without permission using fake numbers, but they sometimes fail to collect on those penalties, according to lawmakers, legal experts and public reports.

Such probes are hard enough to carry out in the first place, and chasing scammers over complex telephone networks - and across country borders - is never easy. Adding to the agencies' headaches, federal officials sometimes are required to issue warnings to the initiators of the calls before they can even consider levying fines under the government's anti-robocall law, known as the Telephone Consumer Protection Act.

House and Senate lawmakers have homed in on these loopholes in similar legislative proposals that each chamber introduced, and passed, earlier this year. In a city racked by partisan division, Democrats and Republicans have managed to find rare unity on robocalls, and they announced that they had reached a compromise on a bill last Friday that would give the FCC and FTC more time to pursue investigations and greater ability to issue punishments, according to a draft obtained earlier this month. It could put the bill on track to pass before the end of the year.

"The TRACED Act is an important step in the effort to stop robocalls by ending spoofed calls in which fraudsters conceal their true identity," said Sen. Edward Markey, D-Mass., referring to the Senate version of the proposal written with Sen. John Thune, R-S.D. The House bill is backed by Pallone and Rep. Greg Walden, R-Ore.

Spikes in robocalls - such as the one observed by YouMail last month - typically accompany major national moments, such as the annual April tax filing deadline or health-care open enrollment. This year, at least six states have warned people about health-care-related robocalls, fearing they threaten consumers with the potential for fraud or insurance that covers far less than they anticipated. Robocalls similarly have plagued other elements of the health-care system, imperiling hospitals, doctors and patients, The Post found.

"The quantity of robocalls is alarming," wrote Dean Cameron, the director of the Idaho Department of Insurance, in a public notice in May, adding that residents should always "be wary of any promises of cheap and comprehensive health insurance sold over the phone."

Insurance experts, telecom executives and federal regulators said they could not determine whether the recent barrage of calls seemingly coming from Executive Health, Whitestone Health or other similarly named groups are illegal or offering shoddy coverage. But experts at two call-blocking apps, YouMail and Nomorobo, said the evidence suggests that the calls are linked - and that some of the tactics they adopted are highly suggestive that something suspicious or illegal may be afoot.

In October, YouMail discovered that a single originator may have placed an estimated 288 million robocalls about health insurance. The company produces its tallies by measuring the number of robocalls captured by app users, then using that as a sample to compute a national figure. YouMail then shared the information with USTelecom, a trade group for the industry that tries to trace such campaigns to stop them. USTelecom since has provided information under subpoena to the FCC, an official at the organization said.

Aaron Foss, the founder of Nomorobo, similarly noticed something amiss after analyzing the messages flagged by its users and its own internal systems. His firm helps monitor robocall campaigns with what it calls a "honeypot" - phone numbers it owns but aren't in use by real people. Numbers associated with the health insurance campaign regularly rang his sting operation, he said, a sign it could be breaking federal rules.

"I can guarantee no one has been given express written permission to call them," said Foss, pointing out that federal law requires consent in this case. "If companies are calling into our honeypot, that's usually a bad sign all around."

While those interviewed for this report said they did not consent to being called, it's unclear whether they had inadvertently agreed to receive the calls by signing on to terms of service or other means.

Some of the messages referred people to the same 888 number for more information about insurance. Those who did return the call said they were greeted by a prerecorded voice that asked basic questions about their age and coverage eligibility, before transferring to live agents who did not offer their names. Attempts by The Post to reach managers proved unsuccessful: Agents repeatedly hung up as soon as a reporter identified himself.

USTelecom, the industry trade group, said it is aware of the person they think is placing the calls but declined to identify them or connect them with The Post, citing numerous concerns, including privacy. "With respect to this health-care scam, we have been responsive to government requests," said Patrick Halley, the senior vice president of advocacy and regulatory affairs.

The FCC and FTC declined to comment for this report.

With federal officials and telecom experts left scrambling for a solution, some people have tried to wage their own private war against spam calls. For Boeger, in Houston, he began calling back after one particularly bad week in November, "fed up" that the spam insurance calls sometimes rang him at least five times a day.

In doing so, though, some organizations have been caught in the robocall crossfire. In Franklin, Tennessee, a local health staffing firm called Whitestone Healthcare now displays a warning prominently on its website that it isn't Whitestone Health - the group that appears to be calling consumers incessantly. Mark Hampton, the director of business development, estimates that Whitestone Healthcare fielded 3,000 calls just over the past three weeks from people who mistakenly found his company through Google searches.

Whitestone Healthcare said it reached out to the attorney general of Tennessee, whose office said it lacked jurisdiction, as well as the FCC and FTC. Neither federal agency responded, according to Hampton, who added, "We'd like to see them enforce the fact robocalling is illegal."

Some critics have called on federal watchdogs to be even tougher on robocallers and telecom carriers alike. The bipartisan bill, for example, starts a clock on the country's telephone providers, requiring them to implement technology that will help them snuff out scammers who adopt phone numbers that resemble those they're trying to call, a tactic known as spoofing. But some critics had hoped that Congress would go even further, forcing a wide swath of the telecom industry to adopt those standards on a tighter deadline.

Still, backers say the forthcoming federal bill is a good start, citing the fact that it "will finally give the FCC a lot more leeway," according to Jim Tyrrell, senior director for product marketing at Transaction Network Services, which aids telecom companies.

In the meantime, the robocalls rage on.

Daniel Schuman said he receives 10 to 20 spam calls on a typical day. That has worsened since October, as open enrollment started and the unwanted pitches for suspicious, low-cost health insurance started to roll in.

Schuman said he isn't looking to purchase insurance in the private market. And the Washington-based policy director for Demand Progress, which works on tech and telecom issues, knows better than to hand over his personal information - and sign away consent - to a random person or website. Yet he said he keeps receiving the calls, which he has tried to block and reported to the FCC without much effect.

"It's destroying the ability to receive phone calls and to make them," he said.