Leaders of the effort to repeal California’s new gas tax increase are blasting Republican governor candidate Travis Allen for using money raised to repeal the tax to broadcast ads featuring himself.

A pro-repeal committee controlled by Allen, an Orange County state assemblyman, is spending a $300,000 donation it received this month on radio and video ads in which Allen introduces himself as a candidate for governor and then advocates for repealing the tax.

Other activists behind the anti-gas tax movement say that money was sorely needed for signature-gathering efforts, as the May 21 deadline for submitting signatures quickly approaches. And the state political ethics commission is looking into a complaint about the spending filed by Allen’s campaign rival.

Allen shot back in an interview Monday that the money was “spent in the most effective manner possible.”

But the internecine GOP dispute could have wider implications: Republicans are counting on a gas tax repeal measure to get on the November ballot in order to encourage their voters to go to the polls and support vulnerable GOP members of Congress up and down the state.

Carl DeMaio, a former San Diego councilman who is one of the leading gas tax repeal activists, denounced Allen for the ad spending, calling him a “fraud” and a “snake oil salesman.”

“While we’re struggling to get our last signatures and could use that money, he takes $300,000 and blows it on his own self-promotion,” DeMaio said in an interview Monday. “I’ve got retired grandmothers who’ve done a hell of a lot more on this than Travis Allen.”

Jon Coupal, president of the Howard Jarvis Taxpayers Association, an anti-tax group that’s also involved in the campaign, said he was also unhappy with the money being spent on ads. “We’re disappointed that those valuable resources that were raised for the purpose of helping with the gas tax repeal effort are not being placed directly into the signature gathering phase of the operation,” he said.

Allen launched a campaign for a ballot measure to repeal the gas tax in May 2017, and made the tax a central issue in his campaign for governor. His repeal effort was sidetracked by an extended legal fight with the state Attorney General’s office over the wording of the ballot measure, and it missed its January deadline without submitting any signatures. At the time, Allen said he would support a separate gas tax repeal effort, run by DeMaio and the Howard Jarvis association, which is still collecting signatures.

Earlier this month, the pro-repeal campaign committee controlled by Allen reported receiving $300,000 from PISF Inc., a financial services company in Marin County. The committee has since paid for ads featuring Allen — in one ad, posted to his YouTube channel, he introduces himself as “Travis Allen, candidate for California governor,” and describes himself as “the original author of the gas tax repeal in California,” before advocating for a repeal. Text on the screen notes that the ad was paid for by his gas tax repeal committee.

Allen argued in the interview that the ads were meant to “get the word out” about the gas tax repeal, and not to support his bid for governor. He said he didn’t send the money to the committee associated with DeMaio and the Howard Jarvis association because it is also associated with his Republican rival for the governor’s mansion, San Diego County businessman John Cox. “The last thing I would do is give any money to any committee that has anything to do with John Cox, because I believe in winning,” Allen said, calling Cox a “failed politician.”

Cox’s campaign, meanwhile, has submitted a complaint to the Fair Political Practices Commission accusing Allen of misusing the funds intended to repeal the gas tax to promote himself. Jay Wierenga, a spokesman for the commission, confirmed that “there is an open case involving Travis Allen.”

“Not one penny of it went to collect signatures,” said Cox consultant Wayne Johnson. “The only beneficiary of the $300,000 ad spend is going to be his gubernatorial campaign.”

Good government advocates have argued for years that some ballot measure committees are used as slush funds for candidates to get around finance laws and boost their own campaigns. Kathay Feng, the executive director of California Common Cause, said Allen’s ad “appears to be an attempt to circumvent California’s campaign finance limits.”

“Usually candidates are much more subtle than this,” she added.

Polls show Republican voters strongly oppose the the gas tax, which was championed by Gov. Jerry Brown. It raised the state gas tax by 12 cents per gallon of gas and 20 cents per gallon of diesel, and also charged higher vehicle fees, to pay for road repairs and transit projects.

Allen argued that he was the original advocate behind the gas tax repeal and had helped collect signatures. “My record is rock solid,” he said. “I’m the first one to start the repeal of the gas tax, Carl DeMaio is the one who followed me.”

But DeMaio — who has endorsed Cox for governor — said that wasn’t true and that Allen caused widespread confusion among voters with his repeal campaign. “What he has done on the gas tax is undermining our efforts,” he said. “This guy is just a piece of work.”

The Marin company behind the $300,000 donation, as well as several of its executives, have made donations to both Cox and Allen’s campaigns. While the company gave the maximum amount, $29,000, to Allen’s campaign, there is no maximum for ballot measure campaigns.

“We’ve been talking about getting involved politically for years,” said Lewis Wallach, an executive with the firm. Cox’s and Allen’s campaigns have sparked “our desire to help make changes and not just talk about it,” including by advocating for repeal of the gas tax, he said last week.

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Proponents of the gas tax repeal need to submit 585,407 signatures in favor of the measure by May 21, although political analysts say they’ll likely need hundreds of thousands more to be sure the effort qualifies for the ballot.

The most recent poll in the governor’s race, conducted by the Public Policy Institute of California, found Cox in second place at 15 percent of likely voters and Allen in fourth place with 10 percent. The top two candidates in the race, regardless of party affiliation, will advance in the June 5 primary.