When federal regulators late last year accused one of the world's most popular cryptocurrency platforms of illegally selling $1.38 billion worth of digital money to investors, it was a pivotal moment in efforts to crack down on a fast-growing market — and in the still-nascent industry's willingness to dive deeply into the Washington influence game.

The company, Ripple Labs, has enlisted lobbyists, lawyers and other well-connected advocates to make its case to the Securities and Exchange Commission and beyond in one of the first big legal battles over what limits and requirements the government should set for trading and using digital currency.

Ripple has hired two lobbying firms in the past three months. It has retained a consulting firm staffed with former aides to both Hillary Clinton and former President Donald J. Trump to help it develop strategy in Washington. And to defend itself against the S.E.C., it hired Mary Jo White, a former chairwoman of the commission during the Obama administration.

Ripple is just one of a long list of cryptocurrency companies scrambling for influence in Washington as the Biden administration begins setting policy that could shape the course of a potentially revolutionary industry that is rapidly moving into the mainstream and drawing intensifying attention from financial regulators, law enforcement officials and lawmakers.

“There is a tectonic shift underway,” Perianne Boring, the president of the Chamber of Digital Commerce, a cryptocurrency lobbying group, told other industry lobbyists, executives and two House lawmakers who serve as industry champions, during a virtual gathering last month. “If we don't start planning and taking action soon, we have everything to risk.”

So far, cryptocurrency has been a highly volatile investment, but it is already starting to alter the way individuals, companies and even some central banks do business. Firms like Ripple, which is based in San Francisco, run cryptocurrency platforms that allow customers to make nearly instant global payments through a system that operates largely outside government monetary networks.

Globally, the value of all outstanding cryptocurrency has jumped to about $2.4 trillion — or more than the approximately $1.2 trillion of United States currency in circulation worldwide — from about $200 billion two years ago. This is from an industry that was born only a dozen years ago, when the first cryptocurrency, Bitcoin, was introduced.

As the stakes have grown, so has the recognition that the industry's future — at least in the United States — will be shaped in Washington, prompting the rush to scoop up well-connected advocates.

The board of advisers at the digital chamber is stuffed with former federal regulators, including a former member of Congress and a recent chairman of the Commodity Futures Trading Commission, J. Christopher Giancarlo, who was named to the board of BlockFi, a financial services company that tries to link cryptocurrencies with traditional wealth managers.

Max Baucus, the Democratic former chairman of the Senate Finance Committee, and Jim Messina, a former top Obama adviser, also have recently been named to senior industry posts.

Lobbying disclosure records show that at least 65 contracts as of early 2021 addressed industry matters such as digital currency, cryptocurrency or blockchain, up from about 20 in 2019. Some of the biggest spenders on lobbying include Ripple, Coinbase — the largest cryptocurrency exchange in the United States — and trade groups like the Blockchain Association.

The lobbying burst is one of several recent signs nationwide that the industry is becoming a bigger presence in the economy. FTX, the cryptocurrency trading firm, is spending $135 million to secure the naming rights to the home arena of the Miami Heat.

The billionaire Elon Musk, who hosted “Saturday Night Live” this weekend, was asked about Dogecoin, a cryptocurrency featuring the face of a Shiba Inu dog that was created as a joke but has recently surged in value. “It's the future of currency. It's an unstoppable financial vehicle that's going to take over the world,” Mr. Musk said, before adding, “Yeah, it's a hustle.” The price of Dogecoin plunged nearly 35 percent in the hours after the show aired.

With the industry's hires of recent government officials, claims of conflicts of interest are already starting to emerge.

Jay Clayton, who was the S.E.C. chairman until December, is now a paid adviser to the hedge fund One River Digital Asset Management, which invests hundreds of millions in Bitcoin and Ether, two cryptocurrencies, for its clients. Mr. Clayton declined to comment.

The day before Mr. Clayton resigned from the S.E.C., the agency filed a lawsuit against Ripple Labs, which competes with Bitcoin, alleging that the company had improperly raised $1.3 billion from investors through what the agency claimed was effectively an illegal stock offering.

Binance.US, which runs a cryptocurrency exchange, this month hired as its chief executive Brian P. Brooks, who until January served as the acting head of the Office of Comptroller of the Currency, which helps regulate banks. The day before he stepped down, the agency granted a conditional charter to Anchorage Digital Bank, making it the country's first national cryptocurrency bank. A spokeswoman for Mr. Brooks said Binance was not a bank, so there was no conflict.

Ripple's new lobbying firms include one that was recently set up by K. Michael Conaway, a Republican who until this year served as a House member from Texas and helped push pro-cryptocurrency legislation last year. Mr. Conaway is banned from lobbying his former colleagues for a year.

So Ripple has enlisted Mr. Conaway's former chief of staff, who is also a partner at the lobbying firm but is no longer subject to the revolving-door ban, to lobby on bills pending in Congress.

Among the other firms working for Ripple is Teneo — led by Declan Kelly, a former aide to Mrs. Clinton — which has assigned Tony Sayegh, a senior Treasury Department official during the Trump administration, to help shape its communications strategy in Washington.

So far, the industry has not become a big player in campaign contributions, although there are major exceptions, like Sam Bankman-Fried, the 29-year-old billionaire founder of FTX, who donated $5 million in October to a political action committee that backed President Biden. (Mr. Bankman-Fried said in an interview that his donation was not an attempt to influence industry regulation, but that he does want to participate in the discussion.)

The cryptocurrency industry has a long list of lobbying goals, detailed in an eight-page letter sent to Mr. Biden in March that called for the government to settle on a clear set of policies with a “light-touch regulatory approach.”

The regulatory questions relate to at least two key parts of the cryptocurrency industry: so-called tokens, which are the currencies themselves, like Bitcoin, and platforms like Ripple that allow rapid money transfers with these cryptocurrencies, or the buying and selling of them, like Coinbase.

But considerable tension remains over existing federal rules, with public sparring among rival companies like Coinbase and Binance, a sign of how hard it will be to reach consensus on any new regulations.

Industry leaders are at least somewhat hopeful that it will have more support from the Biden administration than it did from the Trump administration, pointing out, for example, that Gary Gensler, the new S.E.C. chairman, taught courses about blockchain technology at M.I.T.

At his confirmation hearing in March, Mr. Gensler said cryptocurrencies had brought new thinking to the world of payments and financial inclusion. However, he indicated that he would strike a balance between encouraging new financial technology to flourish and protecting investors.

The cryptocurrency industry is less optimistic about Treasury Secretary Janet L. Yellen, who expressed deep concern this year about Bitcoin.

“It is a highly speculative asset, and I think people should beware, it can be extremely volatile,” Ms. Yellen said at a New York Times DealBook event in February. “And I do worry about potential losses that investors in it could suffer.”

One sign of the industry's growing clout in Washington came during the closing days of the Trump administration, when the Treasury Department proposed a rule to curb the use of cryptocurrencies for money laundering by requiring companies handling certain transactions over $3,000 to know the names and addresses of the customer and the recipient.

Even before Treasury Secretary Steven Mnuchin announced the proposed rule in December, he was targeted in industry appeals to delay or abandon the idea.

“In the early days of the internet, there were people who called for it to be regulated like the phone companies,” Brian Armstrong, the chief executive of Coinbase, wrote on Twitter in November, adding that he had sent a letter to Treasury to object. “Thank goodness they didn't.”

Thousands of such comments have been sent to Treasury.

Among those raising concerns was Sigal Mandelker, who until late 2019 was the top Treasury official overseeing the financial crimes agency that proposed the tighter rule, after her departure. She now works for Ribbit Capital, which is an investor in Coinbase and other cryptocurrency industry players and joined the chorus objecting to Treasury's plan. Ms. Mandelker did not respond to a request for comment.

Mr. Mnuchin backed down and pushed off final action to the Biden administration, which has extended the comment period and is considering how to proceed.

The Ripple enforcement case brought by the S.E.C. in December centers on whether a digital asset the company sold, called XRP, should be defined as a security or a commodity, a major distinction in terms of regulation.

Ripple asserts that XRP is effectively a currency, and like any currency or commodity can be bought and sold without S.E.C. intervention. But the agency argues that each sale of XRP is like a stock or bond trade, meaning a buyer is effectively acquiring a stake in Ripple when purchasing the asset. As a result, the S.E.C. argues that Ripple should have registered with the agency and provided extensive public disclosures like those required with stock or bond offerings.

Ripple, which in 2019 became one of the first cryptocurrency companies to open a lobbying office in Washington, has aggressively pushed back, successfully asking a federal judge to force the S.E.C. to turn over what the agency considers confidential internal documents.

Stuart Alderoty, Ripple's general counsel, said that in the absence of clear cryptocurrency rules, the federal government was effectively creating regulatory policy via enforcement, an approach that is confusing and harmful to investors and the industry.

“If you have a responsible player in the industry, they are going to be engaging with policymakers,” he said.

The S.E.C. case against Ripple has helped persuade industry players on the sidelines to get involved.

“The industry needs to accept that good legislation and regulation is what is required, not no regulation,” said John E. Deaton, a lawyer who has moved to intervene in the enforcement action against Ripple. “Because right now it is like the Wild, Wild West, and you have different federal agencies fighting over which one has jurisdiction.”

The House this month passed a bill backed by industry lobbyists to create a working group of federal regulators, industry executives, investor protection groups and others to examine possible frameworks for a regulatory system.

“We need to get the big prize done,” Representative Darren Soto, Democrat of Florida and a member of the Congressional Blockchain Caucus, a group of lawmakers working with the industry to help promote cryptocurrencies, told the industry conference last month. “Which is the statutes and jurisdiction and definitions to create that certainty, to really let blockchain and cryptocurrency flow and improve in the United States.”