The new digital spot, shared first with The Hill, criticizes Rohrabacher for his ties to Russia. The New York Times reported last year that the FBI warned Rohrabacher, considered one of the most Russia-friendly lawmakers in Congress, that Russian intelligence had been trying to turn him and had even given him a code name.

"America, let’s show Trump and Rohrabacher it's time for a leader who represents us, not Russia," the ad's narrator says.

Rohrabacher has brushed aside any criticism about his stance on Russia, arguing that expertise on Russia is vital for his role as the head of the House Foreign Affairs Subcommittee on Europe, Eurasia and Emerging Threats. And he's said that the issue isn't important to his constituents.

"My constituents couldn’t care less about this. They are not concerned about Russia. They are concerned about the taxes on their home. They are concerned about illegal immigrants coming into their neighborhood and raping people," he told the Times last year.

But Rouda and other Democratic primary candidates, including stem-cell researcher Hans Keirstead, have pointed to the issue on the primary trail.

Rouda wrote a letter last year to the FBI asking them to look into Rohrabacher's "political and financial ties to Russia" in light of news that the congressman traveled to London to meet with Julian Assange, whose website WikiLeaks released internal Democratic emails that intelligence agencies say were hacked by Russian actors.

This week, the congressman asserted that he will still run for reelection, despite two high-profile retirement announcements by fellow California Republicans in the past days.

"I am unequivocally running for re-election and confident that my views reflect the values and the needs of my constituents here in Orange County," he said

"I’ve never run away from a fight over things I believe and I’m not about to start now."

Rouda and Keirstead have been the top two Democratic fundraisers in the crowded primary, which includes six candidates who have raised more than $150,000.

Campaigns will release their final fundraising reports from 2017 by the end of the month, but Rouda's campaign told The Hill he's raised $1.2 million through the year and has $830,000 in cash on hand.

California Democratic House hopeful Harley Rouda is taking the accusations of Russia collusion to his potential opponent, Rep. Dana Rohrabacher (R-Calif.), in a new ad that frames the congressman as part of a joint effort withto side with Russia.