Former Commerce Department official Ro KhannaRohit (Ro) KhannaLawmakers worry about rise of fake video technology Overnight Finance: GOP eyes vote to fund government through March 23 | How much credit should Trump get for economy? | Dems vow to repeal parts of GOP tax law | Mulvaney shakes up office policing racism in lending Dems vow to repeal parts of GOP tax law MORE (D) knocks Rep. Mike Honda (D-Calif.) in his newest ad, the first time Khana has publicly gone negative against Honda in their race.

"First, Mike Honda stubbornly refused all debates. Now Honda's slinging mud, launching false attacks. Isn't it time to put the old politics aside?" the ad says, referencing a recent mail piece in which Khanna attacked Honda.

The spot then touts newspaper endorsements of Khanna, saying he's "for our future."

The well-funded Khanna is looking to make the runoff against Honda in the all-party June primary in the heavily Democratic district.