(CNN)While the investigation into the Trump campaign's ties to Russia and Russia's meddling in US elections has topped the headlines, Democratic midterm candidates across the country have found it difficult to engage swing voters on those topics.
Dana Rohrabacher rival takes on his ties to Russia with help from Seinfeld star
But the contenders challenging Dana Rohrabacher in California's 48th District believe they've got a special case in the quirky Republican congressman, who has persistently advocated for closer US relations with Russia and claims to have once arm-wrestled Russian President Vladimir Putin.
With less than two weeks before California's June 5 primary, Democratic candidate Harley Rouda, who likes to refer to Rohrabacher as "Putin's favorite congressman," is taking a wry look at some of Rohrabacher's odder statements -- highlighting the Orange County congressman's unusual Russia connections with a light touch in a new digital ad featuring former 'Seinfeld' star Jason Alexander.
Rouda enlisted Alexander, who played the infamous George Costanza on "Seinfeld," to serve as his moderator in a mock debate with Rohrabacher, who appears in television clips from an iPad-style screen mounted on the podium opposite Rouda in the mock debate.
Alexander introduces Rohrabacher as appearing "from a secure server in Moscow," as the screen shows a past clip of Rohrabacher abruptly cutting off a television interview by waving and repeatedly saying "good bye."
The digital ad then features clips of Rohrabacher refuting the notion of climate change, calling it a "total fraud" and suggesting that past climate change cycles were caused by "dinosaur flatulence," and also taking on Planned Parenthood.
While the Russia probe has dominated the headlines for the past year, interviews with voters in CA-48 by CNN have underscored that it is not a top-of-mind issue. Several of the Democratic contenders, including Rouda, have argued however that Russia relations have distracted Rohrabacher from more pressing issues facing the district.
On Election Day, Rouda believes that Rohrabacher's ties to Russia will be an important issue that galvanizes voters on the left. And in a race with margins this tight, the level of Democratic turnout is likely to be the most pivotal factor in determining which two candidates advance to November.
"I think it does cut across the political spectrum. When you start with the Democrats on the left, this is a really important hard topic -- in that he's unfit for office," Rouda said in an interview with CNN after a debate with other Democratic contenders earlier this year.
For other voters, Rouda said that when he reframes the question to ask how "Rohrabacher's efforts to build a better relationship with the Russians -- how is that impacting jobs in the 48th district? How is that helping families in the 48th District? It doesn't," he said.
"And then they start waking up and saying, 'Yeah that's not creating jobs here, why is he spending so much time on that instead of focusing on the real issues that we have here in the 48th District?"
Rohrabacher's campaign did not respond to a request for comment.
At the moment, Rouda is battling contenders on two fronts because of the complications of California's jungle primary. The presumption here is that Rohrabacher will easily glide through the primary, where the top-two vote getters advance to November. (Rohrabacher won his 15th term with 59% of the vote; but Hillary Clinton beat Trump in the district by less than 2%).
The real fight this primary season has been for the number two slot.
On the Democratic side, Rouda has been locked in a fierce battle with Hans Keirstead. Both men have been up on television with ads, but Rouda has the advantage of being part of the Democratic Congressional Campaign Committee's "Red to Blue" program.
Just this week, Rouda's campaign and the DCCC put about $400,000 behind a joint ad touting Rouda's advocacy for Obamacare, climate change, women's equality and "fighting the NRA."
To prevent a scenario where Democrats get boxed out of both slots in the top-two primary, the DCCC's independent group has also been hammering Republican Scott Baugh with negative ads.
As of Tuesday, the DCCC's outside arm had run more than $1 million in negative ads against Baugh on Rouda's behalf.