Mr. Larsen, an investor in and executive at the crypto-related firm Ripple Labs, called the attacks on Mr. Bores by a super PAC aligned with OpenAI “really despicable.” OpenAI has called for limited federal regulations to allow the “freedom to innovate” and has generally opposed state regulations like those written by Mr. Bores.

“They are trying to destroy and intimidate and send a clear message that if you do come up with clear guardrails, we are going to crush you,” Mr. Larsen said in an interview. He said he hoped his spending would provide a counterweight: “While some of these folks are going to try to crush you, others are going to step up, and we’re going to support you.”