A Republican senator just gave Libra its first voice of support in Congress after its rocky start with regulators and partners

• South Dakota Sen. Mike Rounds came out as Libra's first major supporter in Congress on Thursday.
• Senator Rounds wrote a letter to Libra Association member Anchorage praising the company's "entrepreneurial spirit."
• Other Libra backers including PayPal, Mastercard, and Visa recently backed out of Facebook's cryptocurrency project.
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South Dakota Sen. Mike Rounds has become the first major supporter of Libra, Facebook's venture into cryptocurrency.

On Thursday, Rounds sent a supportive letter to Libra Association member Anchorage, a San Francisco-based company that describes itself as a "digital asset custodian." Anchorage tweeted the letter, saying that it is committed to continuing to work with Libra.

Rounds positioned Libra as a necessary development that would allow US tech companies to continue competing with Chinese companies. He wrote that he sees a future in cryptocurrencies and digital payments, so he doesn't understand his colleagues' "hostility." According to Rounds, more than 80% of Chinese consumers used digital payments in the last year, compared to fewer than 10% of US consumers.

Rounds also addressed the importance of regulation from Congress for Libra moving forward and supports expanding US anti-money laundering law to cover cryptocurrency, but he slammed the "archaic and inflexible nature of our regulatory and legal system" that drives companies to incorporate internationally.

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In a statement to Business Insider, an Anchorage spokesperson wrote: "Anchorage is grateful to Senator Rounds and the state of South Dakota for their support of entrepreneurship and innovation. Along with the Libra Association's other Founding Members, Anchorage welcomes regulatory feedback and remains committed to working closely with policymakers, at home and abroad. We respect the critical role that regulators will play in Libra's launch. We hope that Libra's ambitious mission will inspire them as much as it has inspired us."

Facebook and Rounds' office did not immediately respond to Business Insider's requests for comment.

Rounds wrote that it was "profoundly disappointing" that other lawmakers responded so negatively to the cryptocurrency, which he fears could "put a chill on innovation in the long run." In July, 5 members of the House Financial Services Committee wrote a letter to Facebook CEO Mark Zuckerberg and other executives to put Libra plans on hold until Congress and regulators had a chance further examine the cryptocurrency. Zuckerberg is scheduled to testify about Libra before Congress on October 23.

That increased scrutiny may have scared off more than a quarter of the project's backers, including Mastercard, PayPal, Visa, and eBay.