A major utility company in California is taking a defensive stance against billionaire Tom Steyer’s campaign for governor, which includes a plan to dismantle electric monopolies.

Pacific Gas & Electric (PG&E) has invested nearly $10 million into an anti-Steyer political action committee, Californians for Resilient and Affordable Energy, according to recent state campaign filings.

This PAC is also backing another committee, California Is Not For Sale, which has been running a series of ads targeting Steyer.

The latest advertisement capitalizes on a misstep Steyer made during a debate last Wednesday, where he remarked, “me paying more taxes is not the answer.”

Steyer’s campaign emphasizes increased taxes on the wealthy, and he has also proposed breaking up the state’s energy companies as part of his progressive agenda.

In his campaign, Steyer has consistently portrayed PG&E as a key adversary. A December campaign ad features him expressing strong disapproval, declaring, “PG&E really p***** me off.”

He blamed California’s sky-high energy bills on the corporation and pledged to cut utility rates by 25%.

The way to do that, he said, is to break up “the monopolistic power of utilities.” The proposals could end up being a threat to investor-owned utilities.

Truly taking on PG&E, however, may be more politically challenging than Steyer’s ads may make it out to be.

Even state Democrats effectively derailed legislation last week that would have helped cities move away from PG&E toward publicly owned utilities.

The ads ran by the anti-Steyer PACs haven’t made much mention of Steyer’s utility plans. Instead, they criticize other issues such as proposed tax increases.

The utility company in response to Steyer’s utility proposals said it is already delivering energy “at lowest possible cost” and pointed to a $12 drop in typical residential monthly bills over the last two years, PG&E told SFGate.

Steyer remains one of the leading Democrats in the governor’s race thanks in part to more than $100 million of his own money he’s poured into his campaign.