WASHINGTON — Rep. Katie Porter (D-Calif.) is taking hits from all sides in California’s increasingly contentious Senate race, facing an onslaught of TV advertising backed by wealthy donors who are seeking to ensure that she doesn’t qualify for the top-two runoff election against front-runner Rep. Adam Schiff (D-Calif.) in next month’s primary.

On Monday, a super PAC funded by cryptocurrency billionaires unleashed a multimillion-dollar barrage of advertising against Porter, accusing the progressive congresswoman of accepting contributions from the pharmaceutical and banking industries she is known to regularly lambaste in Congress. The group, called Fairshake, criticized Porter and said she “says one thing and does another.”

Porter has made fighting the influence of dark money a central part of her pitch in California’s all-party “jungle primary” for Senate. She’s sworn off accepting donations from corporate political action committees, advocated for getting rid of earmarks, and proposed legislation banning government officials from owning financial stocks. Last week, Porter joined other Democratic lawmakers in expressing concerns to federal regulators about the effects of cryptocurrency mining on climate change, which may have provoked the industry’s ire.

“Californians aren’t fooled,” Porter wrote Tuesday in response to the super PAC advertising. “Shadowy crypto billionaires don’t want a strong voice for consumers in the Senate. They fear people who call out corporate greed, so they’re spending millions on dishonest dark-money ads against me.”

She added, “Their ads will never stop me from fighting for YOU.”

Meanwhile, California’s notoriously expensive airwaves are also being flooded by ads from Schiff and a super PAC supporting his campaign. They seek to boost the leading Republican candidate in the race, former baseball star Steve Garvey, and ensure that he makes the runoff instead of Porter, who would likely pose more of a challenge to Schiff. Polls have shown Garvey and Porter battling for second place in the primary after Schiff, with Rep. Barbara Lee (D-Calif.) — who shares Porter’s progressive politics — further behind.

Last week, the pro-Schiff PAC began airing Fox News ads that denounced Garvey, who voted twice to elect Donald Trump as president, as “too conservative for California,” in an attempt to boost his standing with the network’s conservative audience. Porter has called the tactic “brazenly cynical,” and accused Schiff and his allies of attempting to keep a woman from being competitive for the seat vacated by Sen. Dianne Feinstein, who died last year, and currently occupied by Sen. Laphonza Butler (D-Calif.).

Garvey, who has just over $300,000 in cash on hand, would not be able to fund such an ad campaign on his own.

In the Senate contest’s second televised debate Monday, Porter took another swing at Schiff over his advertising strategy during an exchange about instituting upper age limits for elected officials, an idea that she said was worthy of discussion.

“As Mr. Schiff well knows, that is true that we have gerrymandering and elections that are deeply blue districts in which there really aren’t competitive elections,” Porter said. “In fact, he’s hoping that the Senate race turns into one with his ads that he’s running right now.”

Porter trails Schiff in endorsements from establishment voices in the state — including most recently the Los Angeles Times’ editorial board and several high-profile Democratic politicians, like former House Speaker Nancy Pelosi and former Sen. Barbara Boxer. Although she previously pledged to stay neutral in the race, Boxer came out to back Schiff earlier this month, citing Porter’s attacks on Schiff over his accepting campaign contributions from corporate PACs in the past.

Unlike the other Democrats in the race, Schiff is viewed as more aligned with the establishment wing of the Democratic Party. Over his more than two decades in office, he has at times taken votes against progressive priorities, including on matters dealing with taxes and consumer finance regulation. As he began his run for Senate in 2023, he tried to join the Congressional Progressive Caucus after years as a moderate. He’s also sought to appeal to progressives by endorsing “Medicare for All” and the Green New Deal.

But the biggest challenge for Schiff’s competitors may be their fundraising. California is the most populated state in the U.S., complete with 14 media markets, including two of the 10 largest in the country.

Schiff started with a big advantage: He’s known nationwide for sparring with Trump, as well as serving as an impeachment manager for his Senate trial and being booted by Republicans from the House Intelligence Committee — two positions he originally gained as a close ally of Pelosi’s. His notoriety allowed him to build up a massive war chest of $35 million, far more than any other Senate candidate in the nation.

Porter, on the other hand, has turned viral committee hearing moments — in which she dressed down CEOs with a whiteboard and a marker — into a steady flow of small-donor contributions. But she ended 2023 with far less cash on hand than Schiff, at a still-impressive $13 million, leading to a lopsided messaging war that could result in her falling short in the primary.

“She simply is not being competitive with Schiff in the fundraising department,” veteran California Democratic strategist Garry South told HuffPost. “She just wasn’t as well known statewide. She’s way behind on the money front. The last time I checked, she’s about half the level he is on TV.”

South also argued that Porter’s rationale for keeping a woman in the Senate race, in response to Schiff’s ads boosting Garvey, was undercut by the fact that two leading California Democratic women have endorsed his campaign.

“If you’re a woman and don’t know much about Porter, with Pelosi and Boxer giving Schiff their seal of approval, it just basically makes her woman pitch ring hollow,” he said.

California’s primary is set to take place March 5 on Super Tuesday. The top two candidates on the ballot will advance to the general election, regardless of party affiliation.