The ever-worsening scourge of robo-calls is receiving renewed attention in Congress, where top Democrats and Republicans this week are set to take an early step toward cracking down on scammers who prey on consumers’ phones.

The newly revived effort in the Senate takes aim at those who disguise their attempts to steal Americans’ personal information — often by using phone numbers that appear similar to those they’re trying to target. These fraudulent, illegal calls comprised roughly a quarter of the 26 billion robo-calls placed to U.S. mobile numbers last year, according to one industry estimate.

Under bipartisan legislation, called the TRACED Act, the U.S. government would gain more power to slap these lawbreakers with bigger fines, while prodding AT&T, Verizon and other carriers to improve their technology so that consumers can more easily figure out if calls are real or spam. The first test for the bill arrives Wednesday, when it is scheduled to come before the tech-and-telecom focused Senate Commerce Committee for an early vote that it’s expected to pass.

“We absolutely must target these scammers as they present a unique, pernicious threat to tens of millions of unsuspecting consumers they seek to defraud,” said Sen. Edward Markey (D-Mass.), has sponsored the bill with Republican Sen. John Thune (S.D.).

The Senate proposal has broad support from some wireless carriers, public-interest advocates, the makers of popular call-blocking smartphone apps and state attorneys general. They see the TRACED Act as a long overdue attempt to grant consumers a robo-call reprieve, even if it is limited in scope — and isn’t going to alleviate a national telecom nightmare overnight.

But the bill’s drafters and their allies face their toughest challenge in Congress, where lawmakers long have been faulted for acting too slowly to tackle some of the digital age’s most intractable problems, even in the face of widespread consumer disgust.

“I think there’s enough bipartisan frustration with the way things are, and enough feedback from constituents, that the time for action is now,” Thune said in a recent interview.

In the absence of federal action, robo-calls have skyrocketed in recent years, as scammers try to deceive consumers into surrendering personal information, especially during major national events, such as Tax Day later this month. In record numbers, robo-call recipients have regularly complained to the two U.S. agencies that keep watch over the industry, the Federal Trade Commission and the Federal Communications Commission, each of which has issued major fines to the worst offenders in recent months.

But critics say the FCC, as the nation’s chief telecom regulator, still has not acted aggressively enough to halt the deluge. Asked if the agency has been too slow to adopt new rules, Thune, a Republican, replied in an interview: “I would say that’s probably a fair assessment.”

In response, the bill he drafted with Markey would give the FCC more time to investigate robo-call scammers and make it easier to bring bigger fines. Under existing law, the agency is hamstrung: It currently has a year to conduct such a probe and take legal action, a short statute of limitations that the FCC itself has said has hurt their enforcement efforts.

The FCC also often can’t issue financial penalties for illegal robo-calls until it’s given a legal warning to fraudsters who, by nature, aren’t likely to listen in the first place — a requirement that the Senate’s bill would eliminate.

The proposed law would also set regulators’ sites on carriers, including the big four, AT&T, Sprint, Verizon and T-Mobile, giving them 18 months to incorporate new technology in their networks that can verify if a call is coming from a real, operable number. The system, known to industry insiders as STIR/SHAKEN, could result in wireless carriers displaying more useful warnings to customers whenever they’re receiving a suspicious call.

All four carriers have pledged to adopt the technology, but consumer groups fear their timing could slip into 2020 or beyond absent a mandate from Congress. While experts say the technology alone isn’t likely to stop robo-calls entirely, lawmakers still hope to speed it along -- and ensure that smaller phone operators across the country do so, too.

“This is something we’ve been calling on the FCC to do for years, to require phone companies to implement this technology,” said Maureen Mahoney, a policy fellow for Consumer Reports.

Nothing now prevents the FCC from mandating that the country’s telecom carriers adopt technology to authenticate calls, but so far FCC Chairman Ajit Pai has issued only a warning to the telecom giants that the agency would “consider regulatory intervention” if companies don’t deploy it by the end of the year.

Asked Monday about the FCC’s approach, Will Wiquist, a spokesman for Pai, said it would be “slower” if the FCC acted instead of Congress to mandate the carriers adopt call authentication technology, adding agency action “opens the door for litigation that could further delay progress.” Pai previously has praised the legislation.

A report Friday from the Wall Street Journal only added to the FCC’s headaches, revealing that government has failed to collect on some of the multi-million dollar fines it has announced against illegal robo-calls. The FCC’s Wiquist said that it is up to the Justice Department to follow through and collect those penalties.

Pai’s approach drew a sharp rebuke from Democratic FCC Commissioner Jessica Rosenworcel, who said in a statement this week that the agency’s “robocall efforts have barely moved the needle.” Urging her fellow commissioners to act more aggressively against robo-calls, she said of the new legislation in Congress: “There’s no doubt more authority from this act is a good thing — and I welcome it.”

Even the bill’s backers, however, concede the new proposal isn’t going to end unwanted robo-calls outright. Technology to authenticate calls isn’t likely to stop scammers who buy real phone numbers and use them to assault consumers. Nor does the measure address the credit-card companies, student lenders and other legitimate businesses that also ring consumers’ smartphones and landline numbers — legally, if undesirably — throughout the day.

Limiting those calls would require a wholesale rethinking of the nation’s telecom laws, experts said.

In the House, one bill — introduced by Democratic Rep. Frank Pallone (N.J.) — would give consumers new power to stop debt collectors from contacting them. But Pallone, the leader of the House’s top telecom-focused committee, declined via a spokesman to be interviewed. The spokesman did not give a firm timetable for the bill.

The issue also has been teed up at the FCC, where debt-collectors and others have urged the agency to grant them greater ability to call consumers en masse. The FCC declined to comment on its timing, despite seeking public comment on robo-call reforms over the past year.

Aaron Foss, the founder of the call-blocking app Nomorobo, said the TRACED Act at least “gives people a little bit of hope, for a little bit of time.”

“I really think everybody should come together and look at the problem holistically," he added, "and in many ways, hit the reset button.”