Katie Porter pulled a Trump move after losing. Democrats are livid.

Fellow Democrats are excoriating Rep. Katie Porter for saying her opponents, including rival Rep. Adam Schiff, sought to “rig” California’s Senate primary — language that echoes former President Donald Trump’s election denialism.

Porter finished a distant third in the Super Tuesday contest behind Schiff and Republican Steve Garvey. The swift reaction to her social media outburst underscores how California’s enormously expensive Senate race — for a likely safe Democratic seat — has left lingering bruises. It also raises warnings for Democrats tempted to use rhetoric they’ve condemned as undermining public trust in the nation's elections.

Porter's claim spurred an indirect rebuke from Sen. Brian Schatz (D-Hawaii), who wrote that California’s vote was “not rigged.” And Sen. Alex Padilla (D-Calif.), who formerly oversaw California voting as the state’s top elections official, called the notion “ridiculous” without naming Porter.

“It’s not rigged,” Padilla told POLITICO. “As the former secretary of state of California, I can assure you of the integrity of the elections and the results.”

Porter failed to advance beyond the primary after Schiff and a pro-Schiff Super PAC spent millions to buoy Garvey, a former baseball star and first-time political candidate who ran a lackluster campaign. The legal and well-established tactic under California’s top-two primary system nevertheless fueled criticism of Schiff backing a Republican to smooth his path to victory in November.

Porter had already assailed that “brazenly cynical” approach, and she lashed out again on Wednesday in an X post blaming her loss on “billionaires spending millions to rig this election.” She doubled down with a Thursday post saying the vote had been “manipulated by dishonest means.”

On social media, self-identified Democratic voters — including some who said they had supported Porter — expressed alarm that she would insinuate the vote was manipulated.

The backlash was especially notable after a primary campaign in which Porter and other Democrats regularly condemned Trump as an authoritarian threat to democracy. Schiff made that case most forcefully, capitalizing on his fame as an anti-Trump antagonist. The former president repeatedly alleged without evidence that California’s elections are riddled with fraud.

Porter positioned herself as a scourge of moneyed interests that she says corrupt the political process. In addition to facing a spending deluge from the pro-Schiff PAC, Porter was bludgeoned by a cryptocurrency industry offensive.

California’s primary system allows the top two finishers to advance to the general election regardless of their party affiliation. As a result, candidates regularly spend money to elevate a rival who is seen as easiest to beat in the general election. Schiff can now look to an almost-certain November victory over Garvey in a state where Republicans have been locked out of statewide office for nearly 20 years.

Schiff is not the first to use that strategy. California Attorney General Rob Bonta, who endorsed Porter and appeared at her election night party, sought in 2022 to build up a more conservative Republican challenger.

Anthony Adragna contributed to this report.